Do you need a laptop?
If not why not an i7 based iMac? It costs the same - 2199.00.
That's a 27 inch display iMac vs the 15 inch display MacBook pro. 27 inch is a lot of real-estate for PT to use.
Additionally the 27" iMac has
2.93GHz Quad-Core Intel Core i7 - 2199.00
The 15 or 17" Macbook pro only has a
2.2GHz Quad-core Intel Core i7 - 2199/2499
So you are getting much more bang for the buck with the iMac.
Personally I am not really a laptop type of person. I was given a 2008 macbook pro, I hardly ever use it.
But if you need a laptop because you do a lot of mobile work, then get one.
ON EDIT - Mac Mall has the i7 imac for 2129.00 right now (3% off with free ground shipping and no tax (depending where you live). I assume they have similar pricing on the MacBook Pro if that is how you decide to go.
See
http://www.macprices.net/imacinteltracker.shtml