Interestingly, I've seen multiple references recently to the fact that Xbox Live's indie games section has an increasing number of non-game programs in it. With no official word on what to call these, commentators seem split between "application" and "app". Which maybe makes sense given that an Xbox is split on the two factors I mentioned above (not handheld, but there's a single, mediated store for programs).
Well, I don't know how sneaky it is, but it happened without me noticing. To judge by the Apple presentation going on right now, an "app" is now something different from an "application". Computers run applications, which can come from anywhere. Handhelds run apps, which come from the mothership. (The Apple presenters seem to be hewing to this very closely, which is why I noticed, but now that I'm thinking about it, I'm finding it fits my intuition.)