Can somebody explain the appeal to me? Not trying to start a flame war, just trying to understand.The size is important for transportation, not for use. I have the 40mm as well as Voigtländer 20mm, and use them when I need to travel light - as in, hiking in the wilderness with already overweight backpack or struggling with airline carry-on restrictions.
A 24mm pancake (which won't have IS) seems a bit redundant with the 24mm 2.8 IS, which by all accounts is a very good lens, has USM and which Canon cut the price to a much more reasonable level. The size seems kind of irrelevant once you put it on a 5D, 6D or other full frame body [...]
If the rumored 24mm pancake becomes reality and is good enough I'll probably get it and start carrying it instead of the Voigtländer, even though I'd sorely miss the 4mm. A *good* 20mm EF pancake I'd pay serious money for.
I'd also love a bit longer pancake, say 70-100mm, especially a close-focusing one so it'd double as a portable macro.