JAcosta wrote in post #4221813
Do it. Put the 16-35 on the 5d so you get the wide end at true 16mm, and the 70-200 on your 30d so you get the extra reach with the crop factor. Do it do it do it

x2 - the 17-40 is one of my favorite lenses on my 5D...was one of my favorite lenses on my 30D too!
Really, you have a lot of variation here:
16-35 on the 5D = ultra wide angle, great for ceremony panoramas, and tight bridal prep rooms, and reception dance floor photos.
16-35 on your 30D = Standard Zoom (though a little on the short side), great for ceremony processional/recessional, group photos, first dance, etc.
70-200 on your 5D = standard telephoto, great for couple's portraits, close ups of the first dance and slow dances, etc.
70-200 on your 30D = long telephoto, great for close ups, candids, details, etc.
With the 17-55 you are limited to only the 30D. With the 16-35, you would have almost the same range on your 30D + extra wide angle range on your 5D.
Makes perfect sense to me...