Wifi on Macbook vs Macbook Pro
The new 450 megabit per second (a.k.a. 3 spacial stream, 3x3) flavor of 802.11n on the Thunderbolt MacBook Pros is very nice, especially when combined with the latest AirPort Extreme and Time Capsule revisions from June that have modern 450 megabit per second 802.11n radios.

The plastic MacBooks and the MacBook Airs are still running the older 300 megabit per second flavor of 802.11n from 2007.