Update for my post. I was sort of right the first time: But then what does the EHCI talk to over the Thunderbolt-PCIe? An EHC? Where? On the Thunderbolt device

Update for my post. I was sort of right the first time: But then what does the EHCI talk to over the Thunderbolt-PCIe? An EHC? Where? On the Thunderbolt device? It appears from details emerging that Thunderbolt really is just an encapsulation connector/protocol. Don't think of it is a USB competitor - it's a USB encapsulator. Think of having a Thunderbolt connector on your laptop but then also in your monitor at home. The monitor has an USB EHCI, a SATA HBA, etc to support a bunch of integrated USB ports and maybe an eSATA connector or two. You get home, connect your laptop to your monitor via Thunderbolt, and new USB and SATA adapters appear in your laptop's PCIe configuration. Thunderbolt is more of an external PCIe bus than a peripheral bus like USB. It doesn't compete with USB for mice or keyboards. But given that eSATA is a far superior connector for storage devices than USB 3 is (NCQ, DMA, RAID, etc), and that Thunderbolt will be able to encapsulate SATA connections, Thunderbolt might compete with USB 3 on at least that level.