You can see some screenshots of how it works in the gallery below. Personally, I've never been too big a fan of any of the "cross-game" social networking services (Xfire is a really popular one that we've talked about before, and a friend invited me to Raptr as well recently), mostly because I already know what my gaming friends are playing, and I've got enough social services running to distract me from my work anyway. And while an ingame browser is kind of nice (EVE Online actually has one built-in to the game), my own browser is already just an alt-tab away (and I've always got Lightheaded when I just need to pull up some game help). It's nice that this one works in more than just World of Warcraft, but really, why bother playing anything else?
So the GotGame software didn't really strike a chord with me, but maybe if your friends are already on it, and you're looking for a more robust ingame browser, it's just what you need. Get Adobe Air installed, and then you can try getting into the beta on their website. Any other ingame browsers that you guys use regularly or, like me, do you prefer that things outside the game stay there?