Two days ago Ars Technica noted a new published report on why FireWire is doomed. And all I can say is, good riddance.
Look, I know the technical arguments. I know that FireWire uses less CPU time because it enables direct memory access. I know that it has faster sustained throughput than USB2, and that it carries more power to its devices. I know that it allows smarter daisy-chaining, since each connection can negotiate its own bandwidth needs and transfer details. Thanks to this fascinating page, I know that FireWire has a better connector design (at least in its original 6-pin plug) than USB does.
I know all of this, and I don't care. FireWire is an unholy pain.
If you hotplug a Firewire device, it can destroy either the computer or the device ("rendered permanently inoperable" is a nice turn of phrase). FireWire's power requirements are high enough that most laptops (even those that include the full-sized 6-pin port) will not provide bus-power while running on batteries, or even at all, requiring users to carry an extra power brick for each device. FireWire devices here at work sometimes conflict with each other--one editing rig in our studios will only recognize the second external hard drive if we first unplug the DV-CAM deck. Firewire is prohibitively expensive, in part because Steve Jobs got greedy about licensing fees. The cards that aren't expensive tend to be flaky when used for pro applications. The FW800 and FW400 standards use completely different connectors, meaning that we have to buy adapters and new cables to use them. And while the USB connector is not a great design, both its host and device sides are still better designed than the flimsy and shallow 4-pin FireWire plug (the little one that most PC laptops accept).
I suspect that it may survive in the audio and video markets for a while--it's still the best way that I know of to get media in and out of a computer without using PCI cards. I'm stuck with it for a while. But I can't wait for someone to come up with a better solution.
Fun fact from Wikipedia: The standard FireWire connector is based on the Gameboy Multilink cable, since it had proven reliable, solid, easy to use, and childproof.