Seagate has begun selling Thunderbolt SATA adapter for portable (2.5") external hard discs.
It allows SATA hard disc to plug into your Thunderbolt port via the GoFlex Thunderbolt Adapter (STAE121). 40% increase in write speed and 13% increase in read speed as compared to FireWire 800 was recorded using a standard SATA hard disc. Higher speed perhaps can be expected if used with SSD.
Its currently for sale in the USA at $99.
I'm eagerly anticipating it in Malaysia. Can't wait to be able to back up my hard drive lots faster. ^_^