Does it cover threading extensively too I wonder? dRuby needs threading to be of use in my opinion. Ruby's lower level stuff never gets the attention it deserves. Makes writing threaded applications a pleasure compared to everything else

Hi. The chapter 5 is dedicated entirely for the threading topic. There is one section where the description is not correct anymore. You can find the detail at our forum http://forums.pragprog.com/forums/198/topics/10553

Yes, a whole section is dedicated to thread-specific stuff like condition variables, mutexes and thread groups.

Makoto also did a really good talk at the London Ruby User Group on this subject. The video of it is on the Skills Matter website: http://bit.ly/HO2zwY

Yea, good talk. I had the pleasure of winning a copy of his book, and it's been a very interesting read so far: I recommend it.