Apple uses multiple vendors in interchangeable ways to make a single product, but rarely if ever do performance specs change when this happens. Not so with the MacBook Air! The Toshiba bits that are inside my Air, from October, are actually slower than those in the latest batch, which house an SSD blade from Samsung. Grumble, grumble. [TUAW]
Slightly more than subtle, 50 read and 35MB/s write differences are nothing to sniff at...I wish there was a way to know which you are getting beforehand. Seems random right now, not like all of them after a certain manufacturers date have the newer one.