send your WordPress.com posts to your Yahoo! Profile via the Yahoo! Updates service.
WordPress.com sends your published blog posts to several places to automatically promote them for you.
You can also choose to send your posts to your Yahoo! Profile via the Yahoo! Updates service.
To enable this feature, you must first have an account at Yahoo. If you don’t already have an account, you can create one at Yahoo’s homepage.
To connect your blog to your Yahoo profile, go to your Dashboard and then My Blogs.
In the “Publicize” column, you’ll find a checkbox for Yahoo Updates. Click on the checkbox, and you’ll be shown a message telling you to authenticate.
When you click the authenticate link, you’ll be taken to Yahoo, where you’ll need to sign in and approve the connection between your WordPress.com blog and your Yahoo account.
Once you’ve approved the connection, each time you write a new post, you’ll see a “Publicize” section in the Publish box on your post writing screen. The “Yahoo! Updates” box there is checked by default to remind you, but you can uncheck it to opt out of sending that specific post to your Yahoo Profile.
Just publish the post as usual, and you’ll see it show up in your Yahoo Profile.