Upload & Sell: On
Age old question.
If you need to shoot now, get the 5DII.
If you have time on your hands, wait for the 6D and decide. If you buy early, you buy at a premium, so you would be waiting on release, reviews, any firmware fixes, then price drop over 4-6 months. I'd say you could easily wait until June for the 6D to account for all of these things.