As I'm working on my book, I'm trying to remain conscious about making it accessible to as wide an audience as possible. This obviously includes the hobbyist and student crowd. As such, I've been working with the VS Express SKUs... and I must say, they kick mucho butt!
Check 'em out here: http://lab.msdn.microsoft.com/express/
Yeah, yeah, I probably sound like some marketing swine, but so be it. I've always been a fan of lightweight programming environments (emacs, csc, and nant was my standard “ide“ until recently), and these certainly feel more lightweight than Enterprise. Shhh... I won't go so far as to say I prefer Express over Enterprise - I haven't used Express enough to make an informed judgement, and I'm sure there are a slew of nifty features that didn't make it into Express - but when you just want to whack out a bunch of code and don't need a fancy shmancy IDE that supports multiple languages, client- and web- programming together, and the like: this dogfood tastes great.