heatmiser has exactly my point and the benchmarks KingYaba posted further my point. I bet when the new one comes out, the benchmarks will show very little difference between 2.2 or 2.4 verses 2.8 or whatever the final GHz will be. (I'm not even sure why everyone even speculates a 2.8, I can see a 2.4, 2.6 and a 2.8 BTO option.)
Speculating beyond that, the new ones aren't going to be "leaps and bounds faster" than the current ones, just like the previous MBPs with C2D processors aren't slouches just because of the Santa Rosa chipset.
Day to day experience will be *exactly* the same, the only difference you may see is a 2 to 5 frames per second increase in games, but what does that matter if you're already getting a playable framerate? (playable meaning steady 40 fps or better)
There is no reason to upgrade to 2.4 GHz unless you are just made of money and don't have anything better to spend it on, or if you want "Bragging Rights" on your purchase.