We've been told from a couple of different places that a new ultra-wide angle lens for APS-C is coming this year. It would be a replacement to the very good EF-S 10-22 f/3.5-4.5. I wasn't told exactly what the new lens would be.
If I had to speculate, I think it would be a constant aperture f/4 lens with IS. If the lens was released for the EOS 7D replacement, perhaps we would also see a build quality bump with something like weather sealing. Just because they've never done it for EF-S, doesn't mean they couldn't start now.
More to come…