Looks like Yahoo has finally taken my advice. (Just kidding!) They are going to launch a VoIP service in partnership with British Telecom. Well this is not confirmed, but one of my readers has this to say:
Yahoo! is launching a product based on their IM client with BT in a few weeks. The client will allow you to make calls to the PSTN from your Yahoo! IM client. Calls will be billed to your home BT phone account and take advantage of any tariffs you have their.
From the archives I have dug up this little piece, The Incredible importance of Instant Message Clients. Earlier, Sylantro had announced that it could use Yahoo IM client for making phone calls from the computers directly.