Aye I'm struggling with the decision myself. I love my EX1+Letus combo, but it's so bulky, large, heavy, ergonically uncomfortable, takes ages to setup and is general a hassle when all I want is pretty images. This is a big consideration for me as I do a lot of run and gun/handheld shooting.
But it does take bloody lovely images.
The 7D seems to get 90% there in a tiny package, that is easy to use, light, small imprint etc. It may not be 100% of the way there but I think it's close enough to be a very viable option and I believe I'm going to get one to go alongside the Ex1, and maybe I'll even come to see it as a replacement.
With the EX1, you have the option of external recorders to get get even better video quality. The SDI connection outputs 10bit 4:2:2. But then you have to deal with the additional cost too.