NaNoWriMo is indeed just around the corner. As a veteran of this wonderfully frantic literary sprint, I have the following advice to offer you.
(1) The minute you commit to doing it, all hell will break loose in your personal life (good or bad). This is a gimme, so carry on.
(2) You will catch at least one cold. Start taking your Ester C now.
(3) A file will probably get corrupted or you'll accidentally do a "delete all" somehow at 2AM. So, backup often. Learn and setup DropBox now so you can upload your work often and then pick up your files anytime, anywhere.
(4) This is the year everyone will want to have Thanksgiving at YOUR place. Tell them all that your oven is broken and they wouldn't want to catch your cold anyway. [Refer back #2.] Offer to bring the cheese and crackers on turkey day. Make a quick appearance at dinner with Kleenex tissues in hand, then go home, and get back to work.
(5) Attending local write-ins is absolutely awesome. These people will become your annual nano friends and some will become friends year round. Don't expect to get too much writing done during many write-ins, however, because you all will be so giddy with excitement, you'll end up goofing around and having a blast. It's okay, just stay up late that night and get in the rest of the minimum word count.
(6) NaNoWriMo is not a good time to start a new job or a diet. Why torture yourself that way?
(7) Don't worry if you don't "win," just be impressed that you got all those words down on the page!