Something that I remember from one episode... Apple Bloom: What could my talent be? Wait a minute...Apple Family...Apple Bloom...apple...apples! That's it! So, shouldn't Apple Bloom get her Cutie Mark by now? Her special talent is apples, so she should get an apple Cutie Mark.
I just read something on another MLP:FiM forum where someone was speculating that they might get their cutie marks this season since the theme of Season 5 seems to be cutie marks and talents. We'll see...
Uhhh...I don't think 'apples' is her special talent lol. Remember The Show Stoppers? Apple Bloom's talent is building/fixing things, which suspiciously doesn't match her name, but then again most of the Apple Family seems to lack that, relative to other ponies at least.
Probably some time this season. A new poster came out recently that had a lot of characters shaded out/blacked out/whatever you want to call it. The CMC were some of the ones that you could see their outlines but not actually see them in full color. So there you go. See Equestria Daily for more information.
