I was in a similar situation months ago. At that time with the rumors of the 5D Mark III coming out, I waited on upgrading from my Rebel XSI. When it finally came out and the hysteria finally died down a bit, I re-evaluated my needs and decided against the 5D Mark III ($3,500 had much weight, but also I thought as for my first FF--which I really wanted to venture into as my next body, I didn't really *need* the Mark III yet).
Before I bought my new camera (5D Mark II kit w/24-105) last month, it was down to either the 5D Mark II or 7D. I chose the 5D Mark II because I wanted to venture into FF and made up my mind on that. Plus, I thought it would be a logically step to upgrade to the 5D Mark III in a few years or its sucessor at that time.
Since you have the $ to spend on some nicer gears, I would vote for the 5D Mark II and then invest in L lens from hence forward. That's what I'm doing. Good luck!