It is difficult to compare USB to Firewire since Firewire is expansion bus while USB is peripheral bus. Firewire speed is guaranted while USB speed is much lower than rated because it runs under protocol. 480Mb/s rated USB 2.0 runs at about half of this speed while Firewire 400 runs at full 400Mb/s (for the reason of guaranteed bandwidth is widely used in broadcasting industry). In addition Firewire does not engage main CPU having own processing unit with DMA ability. For that reason it was removed from Ipod since it posed security risk. Bringing device with Firewire to work might allow to bypass passwords (Direct Memory Access) and plant virus or spyware on the system or to steal company secrets. Big companies would most likely prohibit Ipod as security risk and that would be disaster for Apple. One thing that killed Firewire on (IBM) PC was greed. Apple charged $1 per port for royalties and that's a lot in very competitive business.
I'm not even sure how important speed is since 16/44.1 requires only 1.4Mb/s. Asynchronous operation might be a different story - don't know much about it.
One test for the future will be HDTV. Firewire 3200 could deliver (with 3% overhead) about 3100Mb/s bandwidth - not enough for 1920x1200 at 60Hz. What about Thunderbolt that has about twice the bandwidth of USB 3.0 and is likely to migrate to (IBM) PC ?
I'm not even sure how important speed is since 16/44.1 requires only 1.4Mb/s. Asynchronous operation might be a different story - don't know much about it.
One test for the future will be HDTV. Firewire 3200 could deliver (with 3% overhead) about 3100Mb/s bandwidth - not enough for 1920x1200 at 60Hz. What about Thunderbolt that has about twice the bandwidth of USB 3.0 and is likely to migrate to (IBM) PC ?