It may get firewire working again on your older deck with Windows 7. If the solution on that page works, then the problem is down to Microsoft, not Adobe.
FWIW, it's getting to be pretty well known around these parts that the current implementation of Adobe Customer Service is awful. That said, several Adobe employees, including some Premiere Pro engineers, have been hanging out in the forums recently. This is a big change from earlier releases of Pr, where an Adobe presence was rarely seen at all.
These same folks have also said that Adobe is working to improve their Customer Service. Like the inertia of a large ship forcing it to take a long time to change course, I suspect that it will take a bit longer for Adobe to make that improvement than it would for a smaller company. Don't give up on 'em just yet.
Thanks for all the info. I neglected to mention I CAN capture from my Sony deck through firewire - I just can't preview or output to or through the deck. I will try the Legacy option because at this point I will try anything and I will report back on the outcome.
I hope the legacy driver helps. At the very least it's supposed to improve the speed of the 1394 connection, which may help preview in Pr.