I'm going to buy this for:
Lightzone - I do photography, and this sounds wonderful.
Bookends - PhD student and probably future researcher. I think I'd rather have Papers though.

Not 100% sure.
Contactizer - There are people I need to contact sometimes. I'll use this to replace iCal and Address book, as it does both, and can do several things that sound great, such as looking at all the email associated with a person in your address book.
and maybe Mellel. MS Word isn't something I really enjoy using.

I only like it because it's at least able to write a few maths equations when I need to, and can handle tables from Excel, albeit very poorly. I know there are supposedly "better" apps for writing equations as well, but the equations I write in MS Word look fine to me. Too bad I can't use LaTeX templates. D'oh!