Well, I voted for the 5D for $1,000 but I do agree with the 5DmkII but you'll have to save some more to get there. I have the 5D and love it. The 1DmkII is a little older and smaller screen. The 2" screen is just too small. The 2.5" of the 5D is acceptable but I would much prefer the 3" the 7D has. In some ways the 1DmkII has better IQ but in others the 5D. The 5D wins for skin tones. The 5D has better high ISO performance than the 7D, not by a lot but also better dynamic range.
With the 5D or 5DmkII you'll miss the AF and frame rate of your 7D but for weddings and portraits its fine.
Your best option is to save some more and get the 5DmkII.
Mark