I've have not given my iPad a rest since I got it, which was day 1 for the 3G. I know many people have come to the conclusion that all they needed was the 16GB version but I am a 64GB person and would have purchased a 120 if they made one. I have a Kindle but still use my Pad to read both straight text and my graphic novels/comic books.
The APPs I use most are iBooks (EPUB), Kindle (MOBI), Goodreader (PDF) and ARCreader (CBR). I also have several magazine APPs. LIFE, MacLife, iPhone Life, National Geo, SciFi Now and for Library books there is Bluefire Reader.
For music I tend to use my own collection or Pandora. For news I have the usual suspects, NYTimes, USAToday, NPR, Ars Technica, BBC, ABC, CBS and also Pulse and Flipboard but find myself with Early Edition and AppAdvice more often than not. For playing instruments (my largest collection of APPs) I have narrowed it down to the company Smule (I have all their APPs) and Bebot. I'll put more back on when I set up my folders.
I'm not a big gaming person so I don't spend much on them. I have a few but only buy if they go on sale. I like Spore but only really play Solitaire and Sudoku. When I'm with family we play Life

but not one of my favorites.
For Utilities I use Dropbox, Urbanspoon, Wiki Encyclopedia, ebay. I use Netflix almost every night and started using FilmOn Player.
What I am currently playing with - Corel 'Paint it! Show' (this is a hoot, converts photos into paintings)