I will fourth the sentiments already expressed. Spent a month there in four cities and had no problem at all. Do bring an outlet adapter, but otherwise you should be set. Internet-wise, I was at low-cost hotels at universities for about half my trip, and they didn't have internet (wired or wireless) there. Our place in Beijing did, though, and it worked fine.
Also, cafes are not a bad place to check for wireless options, if there are any around where you're staying. In one city I spent most of an evening in a French cafe/restaurant so I could get caught up on e-mail and chatting with friends.
Hope everything goes well!