I stand corrected. Well then, Firewire is looking pretty dead to me.

It seems Firewire is more expensive than USB, I don't know if that's simply a case of USB having a better share of the market, but I'd guess it's cheaper to make USB hardware (only 4 connectors compared to 6, and a bit more leeway on some of the specs). So for most uses I'd say USB is better (in the same way a Ford Fiesta is better than a Ferrari for going down to the store, it's cheaper and easier to maintain).

But in some markets, like the professional quality, multi-channel soundcard market, Firewire has a better foothold, due to it's higher bandwidth and lower latency. For up to four channels at 96kHz/24bit with 10ms latency, USB still does the trick, since I do that everyday with my M-Audio Fast-track pro, but above that, it seems firewire is the only option if you want to stay external.

I don't think tech-specs are the only issue, price and stability come into play too, I chose a USB sound card (my computer has a Firewire) because it was cheaper than the Firewire counterpart, and I've heard of quite a few problems with Firewire, and the hardware I was buying didn't need the extra bandwidth. The day I need a 16-track, I might dip into the Firewire stuff.

One of the reasons USB is so much cheaper (on the host side at least) is it doesn't require as much dedicated hardware. Firewire uses a dedicated controller, while USB offloads a lot of the heavy lifting to the processor.

And that's one of the USB's weakest sides. The amount of processing power required by USB file transfers is surprisingly large. That means that any heavy applications you have running can affect the speed of your file transfer and vice versa. This is obviously a bad thing when you are handling real time media like transferring video from your camcorder or recording high quality audio and processing it at the same time. If some application requires a lot of processing power suddenly for a short period, it can mean the file transfer didin't get enough attention from the processor and some frames or a second of audio was just lost.

Something similiar actually happened to me last weekend. I was visiting my parents and I offloaded some DVDs I had ripped to their network hard drive from my portable usb hard drive using a crappy netbook. After doing that, I decided to watch one of them on the netbook. I tried to play it from the USB hard drive, but the whole video stuttered like no tomorrow. So I tried over ethernet from the network HDD and it worked flawlessly.

The crappy netbook processor couldn't handle the usb file transfer and decoding the video at the same time. But over ethernet it was fine, even though the theoretical speed is over four times slower (480mbps vs 100mbps).

Obviously this isn't as big of a problem on modern, faster computers, but it's effects can be seen sometimes on them, too.