Funny this is the 1st time I saw this. Had a buddy looking for a 17-40 a few months ago too...
As for the 20D just hang onto it as a backup, always good to have one in your bag. I kinda wish I wouldn't have sold my 40d to pay for a T2i. Having the HD video on 2 bodies was my reasoning but man the build quality on those D models is light years better than the rebels.