There's also some good 2600 discussion in Hackers: Heroes of the Computer Revolution. Personally I found both of them sort of middle quality books even though I admit that Hackers is a kind of required reading. I think I was spoiled for all other computer writing by the extreme excellence of Soul of a New Machine. While I'm rambling on the subject I'll give quick shouts out to Where Wizards Stay Up Late and Kernighan's UNIX A History and a Memoir.
How it Happened, The Idea Factory, Dealers of Lightning, The Innovators, and Weaving the Web are still on the to-read list. If anyone has suggestions of which of those to read first I appreciate it.