I am very much waiting, and looking forward to a new Canon 50mm. I had 2 copies of the 50mm f/1.8, and eventually got rid of both. AF was not quick enough, nor consistent enough for me on either of my DSLRs. While quite sharp stopped down a bit, it lacked absolute sharpnss & sufficient contrast wide open - particularly noticable in low light. The 50mm f/1.8 It also had poor quality bokeh.
Additionally, I've also used the 50mm f1.4 - but I don't like the 'el-cheapo' micro-USM, and the IQ wide open leaves a lot to be desired. I do realise that good shots CAN be had with either current f/1.8 and f/1.4 - but I want a prime lens that is consistent, quick (both in terms of AF and usability) and long-lasting. I ended up using my 100mm f/2.8 macro for portraits and subject isolation more than my 50mm's, even though of course the composition / framing needs to be much different. (I find my 100mm f/2.8 USM macro lens has quick and very accurate AF response).
So... what do I want in a/the new 50mm prime?
- between f/1.4 to f/1.8. (the f/2.8 of the new 24mm and 28mm lenses is a different category IMHO)
- sharp & contrasty wide open, so I can be confident of awesome IQ
- rounded aperture blades (pref 8 to 9 of them) for great bokeh
- study build (eg metal mount, good quality construction materials
- close minimum focussing distance (eg about 0.4m - 0.5m)
- super sharp stopped down
- USM (or... STM if it's a good implementation, though I'd probably prefer USM with FTM focus).
- IS... well, it would be a bonus - but it shouldn't affect any of the above... but I'll happily pay $100 - $200 extra for it.
- Eventual (hoping!) price: definitely below $1000 with IS and below $800 without IS.