I always said that i hate the famous and de-facto book on ruby on rails "Agile web development with rails second edition". Yes, it is written by the famous dave thomas and the man who created RoR but i think that a technical book like that should be written by who knows how to write and most important how to teach to beginners and alike. Sitepoint's books are so. Who write sitepoint's book knows very well how to write and to teach, expecially to beginners of a particular subject. Said that i tell you (believe it or not) that i read ALL the AWDWR book (cover to cover with all its 700 and over pages) and i can say for sure that i didn't learn a lot more than i did for example reading sitepoint's RoR book. Ok i surely learned some advanced concepts but those arguments are easily searchable on internet tutorials and learned from screencasts like peepcode screencasts or rails screencasts (www.railscasts.com). With this i would like to say that we (or at least i) don't need 700 and over pages books on a subject to start with.......we need the basics explained well and then we can learn from all the internet tutorials and screencasts and that is how sitepoint's books are written for me. Today i write ror apps as i did with only the sitepoint's ror book reading. Moreover anyway the agile book is bad written and it explains things very very bad. I think sitepoint's books are the right balance.....they focus on the topic (on the more interesting and useful parts) in a small to medium book and then with those basics you can move on on your own reading a lot more around.
At the end i would like to say that not always are the book written by the "nerds" on that topic the best on that subject....not always are the very long books useful....etc. What do ya think?