A while back, I got the hardback edition of Gamespite's Game Boy retrospective book for the GB's 20th anniversary:

http://www.gamespite.net/toastywiki/...ableOfContents

They review loads of classic Game Boy games in it, going through each one and explaining why it was a classic and how it contributed to making the system itself classic. It also covers some of the competing handhelds (e.g., Atari Lynx) and points out why they never really reached the heights that Nintendo's ultimate handheld did.

It's totally worth the read - and even the re-read; I picked it up again recently and have been thoroughly enjoying the title.