Just got word of this deal, news of it around the blogosphere:

Yahoo is announcing a partnership with Twitter on Wednesday that will bring the services of both companies closer together. Under the partnership, Yahoo users will be able to read their personal Twitter feeds on several Yahoo sites, including the company’s home page, Yahoo Mail and Yahoo Sports. Yahoo users will also be able to directly update their Twitter status from Yahoo and easily share content that they see there with their Twitter followers. Yahoo will also begin including real-time Twitter content on a variety of its sites.

So, Yahoo's answer to Buzz? (Irony alert).