The sixth volume of Gamespite Quarterly went up for sale last week, and mine just came in over the weekend. You should definitely buy it - I am not saying this because I contributed to it, but because it is an excellent book.
Last year, the second volume included a top 40 "best of" list, as voted by the site's forums. It was a damn good selection, but like most such compilations, it was missing some of my personal favorites - no Bionic Commando, and no Snatcher, mostly. This volume is a top 50 list of games that didn't get in the first time around, plus other under appreciated gems. Again, it's a good solid list of stuff, spanning three decades worth of gaming. Most of them are indeed underdogs, the kind that you could occasionally find people list in their "favorite games of all time" canon but not universally loved enough to make a list like this. Stuff like Bangai-O Spirits, God Hand, Ogre Battle, even Deadly Premonition. Entries 40-50 are pretty brief - mine's only 300 words - but the rest are fairly meaty, and anything with an expansive treatise on Zelda II (still the best Zelda game ever made, never to be surpassed) earns extra stamps of approval. Also, I had never realized that the whole part in Area 6 of Bionic Commando, where you have a scale a tower while avoiding a series of rolling balls, may have been a reference to Donkey Kong.
I forgot to write about it last time because I'm inherently lazy and forgettable, but you should also buy Volume 5 while you're at it. Years ago I'd wanted to write an expansive guide to every NES game published, which fell by the wayside because there's just so much junk on the system. This book, on the other hand, concentrates on what's relevant about the system, not just on specific games, but various topics - MSX<->NES translations, the awfulness of LJN (and to contrast, the radness of Ultra), the best Japanese-only games, various bits on censorship and other localization topics, and loads of other stuff. It is basically the perfect book for NES fans, so if you know a video game nerd and don't know what to get them for Christmas, this is probably it. The layouts also look fantastic, especially since their in black and white. (For all of the people commenting on about how it should be in color - yeah, color printing, especially through self-publishing, is still ridiculously expensive.) I can tell you that HG101's Adventure Game book will not look nearly this pretty. (Although, keeping in the theme of the site, it will be at least as large as a college textbook.)