The MBP has the Sudden Motion Sensor - there are a couple of apps that use it for anti-theft. iAlertU is a fun one. You can set it to capture an image from the iSight camera when triggered and email it. I can't think of anything else that's Intel only.
A few other things to keep in mind when going from the PB to the MBP:
If you use the PB's internal modem, you will need Apple's USB Modem.
Any PC Card (PCMCIA/Cardbus) devices, they will need to be replaced by an ExpressCard/34 equivalent. Card readers are the first thing that come to mind. I always kept my SD reader installed in the slot, so I found an ExpressCard/34 that fits flush (Belkin). Delkin makes a CF reader, if you use those.
Connections to a TV will require an additional adapter to go from DVI to composite or S-Video. The PB had a build-in S-Video port and came with a S-Video to composite adapter.
Enjoy your new MBP!