I did exactly that just a few days ago - scored a new 2.4 Ghz Penryn MBP 2GB 200GB for $1200 (after the $200 MSN live cashback deal), pretty insane I think considering it's just as fast as the new one in non-graphics benchmarks. The $800 savings makes it a no-brainer. I also got an Applecare warranty for $145 off of Ebay after the same cashback deal. So for $1345 shipped I'm sitting pretty damn well.
Apple dropped the ball big time on the new MBP release, plain and simple. The case and build quality are absolutely stunning, but seriously, no processor improvement whatsoever over the last generation? Maybe that's Intel's fault more than Apple for now advancing processor design fast enough, but they should have at LEAST gone with a 2.6ghz proc for the basic MBP configuration in the new system, and I think an LCD resolution improvement is long overdue as well when you compare the MBP to other notebooks in it's class. And for all of the fanfare over the new unibody system, the new MBP being bigger and heavier than the old is a step backwards frankly.
Now I'm just waiting for those Intel SSD's to come down a bit.. with one of those my old junker will eat the new MBP's for breakfast.