The page is available on over 300 devices, including the iPhone, for users in the UK and selected locations around the world. The page is customisable, so you can add and remove social networks, webmail, news, bookmarks, weather and more.
The Yahoo Web homepage is designed to function as an Internet portal thingy, and the mobile site does the same. You can add links to sites like Facebook and Twitter for instant access to your networks. At least it's supposed to be instant -- we added Twitter and we're still waiting for it to appear. You can also access Hotmail, Google Mail and AOL Mail, as well as Yahoo Mail.
Like the recently launched BBC mobile homepage, the Yahoo page allows you to customise which areas of news you'd like to see. Unlike the BBC, there will be ads.
Update: Twitter has now been added to our page and is accessible via a neat feature called Social Pulse, which pulls together all your network activity in one feed list. It just takes a while for each service to add itself.