Microsoft has now acquired the search business of yahoo
http://www.businessweek.com/technology/content/jul2009/tc20090728_826397.htm

So what does it mean?

There’s a fairly lengthy explanation in terms of SEO here: http://www.seomoz.org/blog/top-10-things-the-microsoftyahoo-deal-change-for-seo

But what it really comes down to is this:

There are now two main Search players, Bing vs Google, all others will probably either fall by the wayside or be eaten up by one or the other.

Google now has one, very specific opposition, and Microsoft are probably out to give google a very good run for their money.

How they stack up in my opinion:

Google:

Currently have superior presence, both US and internationally, consumers see them as a household name. Their webmaster tools / analytics / adsense management is very well established and easy to integrate with each other.

Bing:

Not a household name yet, webmaster tools etc needs a lot of work, and they do not have even close to the volumes of Google. They do however have one of the worlds largest corporations behind them, with reaches into most major economic centers.

Check out microsoft locations vs google locations to get an idea of local offices:

http://www.microsoft.com/worldwide/default.aspx

http://www.google.com/intl/en/jobs/locations.html

So it will be interesting to see how things play out, the tried and trusted brand or the oversize bully that is able to place it’s product exactly where it wants it, in your face.