2.4 GHz Intel Core 2 Duo processor
2 GB RAM
250 GB 5400 RPM hard drive
NVIDIA GeForce 320M integrated graphics card

Longer Battery Life (63.5 watt/hr)

A few days back I read on TUAW (The Unofficial Apple Weblog) a story where Vietnamese site Tinhte had leaked the details of this update and needless to say they were pretty dead on.