Google never sleeps. After the *silent* addition of the colored labels to gmail, it is now possible to chat with AOL users. Not so long ago I predicted Google would add connectivity to other IM platforms soon, and this is the first one.
It is pretty clear that in a few months, ICQ users will be able to chat using Gtalk and others will follow, too. It is questionable though whether MSN will be added, as Microsoft always had the habit of being in the way of systems that want to connect. Remember how Hotmail used to change it's structure frequently, because other programs and scripts were written against it to enhance usability. A good example was the gotmail script that enabled you to get mail from yourand put it into a unix mailbox, just like getmail. I do hope MS has changed in this respect.
Pretty cool news though. This is yet another example of how Web 2.0 is all about integration and usability.