There's a large amount of evidence pointing to today being launch (including the recent tweets from HMXers). If you're still "severly" doubting at this point you really should just ease up.
i think it's comin today :) yippee!
HMXhenry: I like to think that all this "big day" talk is in reference to the fact that I am bringing doughnuts into the office today.
HMXCasey: RT @johntdrake Big day
Remember, Billboard had the first article on the RBN all that time ago. I'm tipping they let this one out just a few hours early. My money is on it going live with today's Xbox Live Marketplace update.
I'd say it's definitely coming today, now it's just a matter of when.