knee surgery six months post op

I had my RNY the beginning of October 2008.  I'm down over 160lbs so far - which I'm pumped about, but I'm headed in for knee surgery in two weeks.  I'm getting 5-8 bone spurs removed (dr said a weeks recovery) from my left knee and there is the possibility that they may have to shave down the end of some of my long bones (dr said 6-8 weeks recovery) as well, they won't know until they go in.

Has anyone out there had surgery similar to this or knee surgery since their RNY?  How long was your recovery?  What'd you do to stay as active as possible during recovery?  I've got some free weights and thera-band at home I can use before I go back to the gym.  Any ideas for a nice speedy recovery? I've never had knee surgery, and my pre-op appts are all coming up next week, but if anyone has any info or suggesstions they'd like to share, please do!! 

thank you, thank you, thank you!!!
katie