Cross platform integration makes everyone's life simpler.
"From the beginning, we designed Google Talk using open standards so that you could connect to your friends and family using any chat product, making communication as easy as possible. A few years ago, we announced our partnership with AOL which made it possible for people to chat with AIM users right from inside Gmail. Today, we’re happy to report that AOL has now made it possible to chat with AOL contacts across a variety of Google services: not just Gmail, but also iGoogle, Orkut, and Google Talk on Android phones.
If you chat with AIM buddies in Gmail, you’ll notice a few changes. First, you’ll no longer need an AIM account to connect to your friends using AIM. Instead you’ll be able to add your AIM buddies just like you add Gmail contacts to your chat list: using their AOL screennames (for example, email@example.com). AIM users will now also be able to add Google contacts to their AIM chat clients."