Two major upgrades offered to all of Apple's new MacBook lineup are updated SSDs and native USB 3.0 support. The same updated SSD is present across all of Apple's lineup: from the MacBook Air to the next-gen MacBook Pro. Based on the model number in Apple's System Report I'd guess my review sample features a Samsung based drive. Toshiba was a secondary source in the past, and with its announcement of a 6Gbps controller I wouldn't be surprised to find that in systems as well.
http://www.anandtech.com/show/5997/s...ay-macbook-pro