As I’ve noted, unlike the new MacBook, the MacBook Pro revision retains FireWire, in the form of a FireWire 800 port. This does represent a switch to an NVIDIA chipset, so there may be new performance wrinkles with some interfaces. But it’s not the FW800 port per se you have to worry about. It gives you one less physical connector (previous MBPs had both a FW800 and FW400 port), but even the earlier models had just one bus for FireWire, shared between those two ports. There is a little bit of inconvenience there in that you need an adapter cable and have one less port free, but it’s much less of the deal-breaker the MacBook’s lack of FireWire or expansion is.
MOTU had already published a support note out about supporting FW800 ports — executive summary: don’t worry about it. Now Apogee, makers of the Mac-only Duet, weigh in:
Connection between a “late-2008″ MacBook Pro and Ensemble or Duet is made with a commonly available FW800 to FW400 adaptor or cable. The connection of Ensemble or Duet to a FW800 port is fully supported and in no way alters the performance of the interface.
Ensemble and Duet Compatible with New MacBook Pro [Apogee Digital]