It's going on 4.5 months since the unibody MBs/MBPs were introduced. I think that people should wait. Apple updates notebook about every six months on average. I think with Apple's model of two updates annually, you get the best buy as close to release as possible. Toward the end, like now, you're getting 4.5 month old technology for the same price that it cost when released. So waiting a month or two the new model will be updated CPU, possibly graphics or RAM, and other possible speed bump changes usually at same price. With this model, people should buy right when releases are made if they can wait.
This is exactly the way I feel. Why pay the same price for something now that was introduced in October when in 2 months or so, an updated version is likely to be released. This is why I'm willing to wait 3 months if necessary to get my MBP.