Hi Denis,
The Phase IQ Backs are FW800 as well. But they are certainly touting that they have USB3 for future connection.
Apple had their own agenda with Thunderbolt or Lightpeak at the time of USB 3 so obviously they are going to support that beyond USB 3. But it could be included in the future as Intel have officially given their full support to it recently just after the launch of Thunderbolt. But unless there is a widespread embrace of it, which I'm not sure there will be they won't jump on to it. They want to be pioneers of this, and tout it as their format so will push it above all and want to replace all connections with TB. Monitors, drives, all peripherals.
Above all though, Thunderbolt is really way ahead of USB3 so I don't think it will even happen officially.
Phase One could rebadge a third party USB PCIe card when a reliable cross-device one exists. Either that or commission one and develop their own. A couple have surfaced, such as Lacie, but they only work, and limitedly apparently with their own drive. Either that or dump USB 3 for TB eventually. Sadly, not great timing for them at all. Doesn't help on laptops though...and I'm sure most of the big manufacturers see the value of the higher performing TB.
The chances of adapters are possible but not as great as you might think given that TB needs to be implemented at motherboard level. TB itself needs graphics processing also for it to work and it's not even certain if you're going to be able fit a PCIe card to current Mac Pro's. OWC certainly said it won't be possible but others are saying it might be. Kinda sucks don't it?
Apple were just awarded a patent for a multi connection plug that supports USB3 and TB at the same time but for Phase One it depends if the USB3 plug has room for it. It probably will be that it does but just not run at TB speeds.
Who knows with Apple...They said they would never go BluRay and I don't think they will, but that is more to do with economics with iTunes downloads.