Now this is a beauty. Google is in the process of integrating GoogleTalk with GMail.
They're doing this in a number of ways. First off, the much anticipated ability to record your chat history within your gmail account (with the ability to go 'off the record' during any conversation that will prevent both sides of the conversation to stop logging.
More impressively, chatting and presence have both been integrated directly into the gmail interface.
A small presence window shows you your contact list with status messages and presence. Clicking on your contacts will launch a chat window within GMail, which can be un-joined into a separate pop-up window.
It's a very neat combination that looks good and just the way you'd think it should. It's the next logical step in web-based mail and after the disappointment of Google Video it's good to see Google have done this right.
Google say they're rolling this out now, so expect to see it in your GMail interface soon.