I'm not sure if anyone has seen this yet, but in examining the System Profiler on several non Thunderbolt-equipped Mac systems, I've come across an interesting tidbit. It could simply be related to the difference in hardware, but I've decided to be optimistic and infer that it means that the expected Thunderbolt expansion cards for Mac Pro are forthcoming. On computers with no chance of ever getting Thunderbolt, such as Mac minis and older iMacs, the System Profiler reports "No hardware was found." On Mac Pro systems, which will hopefully see PCI-Express based Thunderbolt expansion cards as an option soon, the System Profiler reports "No drivers are loaded." Thunderbolt equipped systems of course report information about the available ports. Examples from a few systems I have: 2009 Mac Pro 8-core 2009 iMac 24" 2009 Mac mini Example from a 2011 i7 iMac with (2) Thunderbolt ports.