Last month, Bing and Yahoo increased their share of total US searches, at the expense of Google.

Google now accounts for 64% of searches, Bing powered search  accounts for 30%. Both Bing and Yahoo are powered by Bing now; Yahoo gets 16% of searches and Bing gets 14%. All the remaining search engines split the remaining 6% of US searches.

Google’s share is down  by 3% last month, Bing’s share is up 6% and Yahoo’s share is up by 5%, continuing the improving trend for the Bing-powered search engines.

The Yahoo/Bing “merger” has happened within the past two weeks in the US and Canada. Searches on both Yahoo and Bing are now powered by Bing’s index and pay per click (PPC) results on both will be combined soon. Both companies see this as a big deal, especially in terms of helping them compete with search goliath Google, which still gets about 70% of all searches.

This doesn’t, however, mean that results on Bing and Yahoo will be identical. While both are using the same index (the list of pages on the web with information about their content and linking), the two search engines maintain different algorithms. That means that different ranking factors are being weighed more or less heavily by each of them.

We can expect rankings in Bing and Yahoo to resemble one another more closely than they used to, but our client rank checking shows they’re still quite different.

Web Pro News has a video news report that goes into more detail on this and some of the implications for SEO.

Google Sites led the U.S. core search market in June with 62.6 percent of the searches conducted, followed by Yahoo! Sites (up 0.6 percentage points to 18.9 percent), and Microsoft Sites (up 0.6 percentage points to 12.7 percent).

Both Yahoo! Sites and Microsoft Sites have experienced gains due in part to the continued utilization of contextual search approaches that tie content and related search results together. For more detail on contextual searches, please read this post on the comScore Voices blog.

Ask Network captured 3.6 percent of the search market, followed by AOL LLC with 2.2 percent. More from comScore here.

At Rank Magic, we’re changing our keyword ranking reports to focus on Google, Yahoo! and Bing alone. We’ve found that including other search engines tends to confuse our clients, and since the three top search engines account for more than 94% of all searches it makes little sense to worry about tracking the others.

We wrote in April about problems with sites created with Yahoo Site Builder: some important SEO techniques couldn’t be applied. Now there’s more.

When we optimize images on a page, there are three opportunities to employ keywords: in the file name, in the alternate text, and in a title attribute. The title attribute shows up in a small text box when you hover the mouse cursor over an image that has one.

A client of ours found themselves unable to create these title attributes, so they called Yahoo Site Builder for help. The person they spoke with didn’t know what title attributes are, so my client asked me to intervene and ask the Yahoo people about it because we could speak the same language. I submitted a help request, and got the following response:

We’re sorry, the feature you are mentioning is not currently available through Yahoo! SiteBuilder and we do not have an estimated date as to when or if it will be available. However, we’ll pass your comments on to our Development team for further consideration.As you Yahoo! Site Builder uses alternate text (alt tags) on images.

Once again, we must conclude that Yahoo Site Builder is not prepared to allow full search engine optimization.

One factor we’ve seen that can hurt your rankings … and that almost no web site owner is aware of … is known by the tongue twister “canonicalization“. It can be fixed by three lines of code, and we explain all that on our web site and in optimization recommendations we provide for our clients.

Unfortunately, Yahoo Site Builder can’t let you implement those simple three lines of code. We ran into this on behalf of a client of ours this month. When I wrote Yahoo for assistance, this is the response I got.

We’re sorry, but the feature you are mentioning is not currently available through Yahoo! Web Hosting, and we do not have an estimated date as to when or if it will be available. However, we’ll pass your comments on to our Development team for further consideration. Since Yahoo! is a share hosting service, we currently do not offer access to .htacess files.

Yahoo and Microsoft have finally partnered in a search agreement, one that’s been expected ever since Microsoft tried to buy Yahoo for 44.6 billion in early 2008. It seems that Microsoft will power Yahoo Search and Yahoo will become the exclusive search advertising (pay per click) provider for Microsoft’s search engine Bing.

Suddenly, the Big Three search engines are only two, with results in Yahoo and Bing being essentially identical. There may be some slight differences, so we’ll continue to track client results in both Yahoo and Bing (as well as several others, of course). In terms of techniques for optimizing web sites, we don’t anticipate any change.

Google’s influence on the web is so powerful that we tend to forget that there are other search engines. The forefather of modern search, Yahoo! still serves around 20% of all internet search queries. This pales in comparison to Google’s close to 70% majority but is spread over a different demographic making it an intriguing prospect for certain types of web properties.

Search Marketing Standard explains that often Yahoo! is more attractive to women, and some research shows that Yahoo! searches sometimes convert to sales better than Google searches. So don’t ignore Yahoo! in your monitoring of results and in your SEO. Read the article at Search Marketing Standard for some tips on how optimizing for Yahoo! may be different from optimizing for Google, especially with respect to meta tags (it pays more attention to these than Google), page structure, alt tags and heading tags, and external links (only closely related links really count for much).

I’ve been hearing increased conjecture about a Yahoo Sandbox, similar to the well known and largely mythical Google Sandbox. People who find it takes many months for their new web site to show up in rankings in Yahoo or Google often assume that these search engines have some sort of “new site filter” that’s keeping them from showing up.

I don’t think that’s it at all. It takes a certain amount of inbound link popularity for these search engines to think your site is worthy of appearing near the top of the list. Not only does it take time to get quality inbound links, but it takes additional time for those links to be all accounted for by the search engines before they accrue any benefit to your site.

Withy that said, and not to denigrate the importance of link popularity in Google, Yahoo is much more weighted in favor of on-page content. If you have plenty of keyword-rich content on lots of value-packed pages (value to the human visitors to your site) then you’ll do better in Yahoo.

Everyone seems to be making a big deal out of the proposed buyout of Yahoo by Microsoft. Even NJBiz asked me to comment on it.

While I suppose it is a big deal in terms of the level of competition, and it may well make Microsoft somewhat more competitive against Google, it’s not going to affect greatly how we do SEO o how people will find your web site in the search engines. Google will either retain the Yahoo brand and the Yahoo search engines, or kill it off and incorporate their technology within the MSN/Live search engine. The relative proportion of searchers who go to Google, Yahoo, and MSN may change a bit, but I don’t anticipate anything drastic.

Bottom line: don’t worry – this is unlikely to hurt your search engine visibility.

For the first time, Yahoo! has replaced Google as the No. 1 portal of choice, according to a customer satisfaction survey reported in Computerworld.

Yahoo’s score is up 4% to 79 on the 100-point scale of the annual University of Michigan American Customer Satisfaction Index on e-business Web sites. While Yahoo’s stock among users is rising, Google’s is on the wane, according to the report. Google fell 3.7% to 78, the second time in as many years that its score declined.

The results indicate a battle brewing between the two Internet giants, but the survey’s author says to keep an eye on Ask.com.