The SATA 6Gb/s Ceiling?

I was talking to a guy in another post concerning his SSD and swapping it to a SATA 6Gb/s controller. The conversation lead to question concerning why he needed SATA 6Gb/s if his SSD only performed at 550MBp/s speeds.

Anyways, I explained about the conversion of bits to bytes and I showed him how 6Gb was really only 768MB. That got me quite concerned.

Current SF2281 SSDs really are pushing sequential writes and reads at over 500MB/s. This is up from less than 100 reads and writes just two years ago.

If SSD technology continues to grow, even at reduced rates we're quickly going to saturate SATA 6Gb/s. We already have cards today that require pci-e lanes in order to reach their speeds like the Revo 3x2. By mid-year we could be seeing single card TLC solutions that approach 1GB/s sequentials for half the cost of todays MLCs.

What then? I know this is an inherent danger especially with fast moving technology, but I can't recall a previous time in which a new standard was so rapidly overtaken. What's the status of SATA 4.0 and at what speeds do they try to work with? 12Gb/s, 24Gb/s? I'm glad thunderbolt is just around the corner.

SATA Express:

http://www.sata-io.org/technology/sataexpress.asp