Only the 200-400mm f/4 - preferably before my trip to photograph Puffins in June - or certainly before Kenya in September
The EF 50mm f/1.4 II USM -- no IS!
24-105L f/2.8 IS II
I haven't waited, I bought what I needed. I would have been waiting for well over five years to get a new 100-400mmL MK II since the rumors started. I'm getting old, I don't have 5 or 10 years to wait