This spreadsheet has a list of YC companies along with whether or not they are dead or have exited: http://spreadsheets.google.com/ccc?key=0AkkhSN3vaY4jdF90b1l1...
I'm about to start work as a new employee at a YC alumni, hopefully we'll do better!
ALL of the exit values (except 1 or 2) are my personal estimates and educated guesses... nothing more. I'm always happy to revise them with better information!
TechStars at least publicizes whether the exits are > or < $2million, which can be a helpful guide...
I'd bet under $10M, probably closer to $5M. Based on me sitting in my chair knowing nothing.
If your guess is no better than the reader's, I think it's best to provide the relevant information you know, and let us draw our own conclusions.