Anecdotally I've heard 8-12 months to finish it AND do all the exercises.
I'm hoping it can be done faster, but I'm committed to the idea that it could take a while given my work schedule.
It was designed as a text for an intro to programming college course, so I'd say it is possible to complete it in four months if you devote an hour to it every night or so.
And here I was thinking it would take me about 2 months to finish it. Anyway, I'd definitely like to participate. Also, take a look at this: http://new.p2pu.org/en/groups/sicp-study-group/
Interesting, this seems to be a better way to organize the process than a wiki :-)
Let me know if you're going to make your own study group.
Just joined up there! Shoot me an email too if you'd like to discuss on Skype as you go along.
dustin [at] myplanetdigital [dot] com
At Berkeley, I did 61A as a summer course (which is based on SICP). Admittedly we skipped a few sections, and of course we didn't do all the exercises, and it was hard to keep up, but if you're wiling to dedicate a reasonable chunk of time to it every day, it's possible to get the material substantially faster than that.
At my school we went through it in about two and a half months (my school did quarters instead of semesters), but I recommend taking more than that.