For starters, I feel your pain, as Davis is my top "realistic" choice. I applied in October, so it's been a long, long time for me too.
Now on to business...one thing you're overlooking is that the status checker tells you how many applications were UPDATED, not the total number of applications in the system. I'm pretty sure Davis usually gets over 5,000 applicants each year (EDIT: I was wrong about this, they only get around 4,000).
With that said, last year they admitted a little over 800 applicants (not sure of exact figure), so the 770 number tells me they still have a few more to go. Good luck, maybe I'll see you there.