my statement regarding 24/2.8 being EF-S rather than EF was meant not so much as a complaint, but rather as "an observation". Maybe my wording was too strong.
After reading the posts here ... I take the point, that for some/many people the 24 pancake may have value as really small, light, tiny, chap and optically decent "general use lens" to take along when you're out birding or to an airshow or to motorsport events etc. with an APS-C DSLR plus long tele lens as your main rig.
While it may serve very well for that purpose, I still believe, the lens has only very limited appeal beyond that scenario. After all it is only "only" f/2.8 - and many serious Canon APS-C shooters already got a 17-55/2.8 and many of those who wish(ed) for EF-S primes are mainly interested in getting primes that are at least 1 stop faster than zooms coverng the same focal length. A still very compact, optically decent and sensibly priced EF-S 24mm/1.8 would have been more interesting.
I am still convinced an EF 24/2.8 could be built quite a bit shorter and smaller than the EF 24/2.8 IS. Using the right lens design and 2014 glass [ED], algorithms, and computing power I think it could be a bit smaller yet optically much better than e.g. the age-old, full frame Pentax FA 20mm (!) /2.8 -> http://www.pentaxforums.com/reviews/pentax-fa-20mm-f28/review.html?src=lrdb#specs
Anyways, it is a "theoretical" discussion. Personally, I am not interested in any 24mm f/2.8 lens, as I already have a faster, extremely compact, optically excellent, very "price-worthy" WA prime for APS-C. Made by Canon, called EF-M 22/2.0
All I want now, is a better camera body to put it on. However, that's a different topic and probably considered "complaining" and "whining" around here.