Yes, agreed many audio interface manufacturers are still producing products with FW, but I believe most major PC manufacturers said they're moving away from FW in favor of USB2 / 3 (I think Apple has rumored something simliar, no?). Either way, it will certainly be around for a long time, given its' large install base - as I said above.
Personally, I would prefer interfaces with multiple connectivity options instead of just FW, but that's just my opinion.
Russ