burrp! has setup a NYE microsite – http://mumbai.burrp.com/nye/ that lists several parties and also offers some tips on what to wear, where to go etc etc.
There is also a Facebook group for NYE 2009 –http://www.facebook.com/group.php?gid=51831587168
… and last but not the least, NYE party updates are now available via Twitter @ http://www.twitter.com/nyeindia/
btw, the Infomedia Cityguide (Mumbai edition) also contains a bunch of NYE parties in Mumbai as well as Goa. I think you can buy it at your local bookstore for Rs.30 only.
Stay happy and stay safe.