Just restarted Firefox, and my gmail tab got re-opened. This is what greeted me. Too cool. I played with the new chat feature, and I have to say that I am pretty impressed. Very slick integration. Easy to use, easy on the eyes, lots of options that make sense and are easy to understand.
Will this replace MSN? No. Will it replace AIM? No. Will I use it? Maybe. If I had more contacts on gmail. Most people I know have their own domain or a shaw/hotmail/yahoo email address.