I just logged into my Gmail for the first time today and as soon as I logged in a full page came up asking me if I want to "Check out Buzz" or "No, go to my inbox".

If this didn't happen to you, it sounds like someone else is checking your email. Edit: maybe you were already logged in...

Anyways it's pretty humorous that you're getting indignant about this new feature being 'installed on your system'. I'm laughing with you not at you though. Don't panic -- it's just a new feature on the site!