No. USB sucks and creates a bottleneck. It causes high CPU load because it doesn't support true DMA in hardware (among other things), relying on the CPU to do all the heavy lifting. This makes it a very poor choice for... pretty much any high speed devices, particularly when CPU overhead is at a premium.
By contrast, while I can think of a good number of FireWire cards and devices that suck, that's not FireWire's fault. That's the fault of people not designing/manufacturing the devices correctly.
FireWire (when implemented correctly) doesn't create much more of a bottleneck than PCI except in terms of raw bandwidth (and FW800 doesn't create much of a bottleneck compared to standard PCI even in terms of bandwidth...). If you're really shoving more than 800 Mbps, then yeah, you should be using something else. For the other 99.99999% of people in the audio world, it is more than sufficient.
If you'd like to point out specific flaws in FireWire, go for it, but I'm guessing you can't. I can---things like taking two computers with heavily loaded FireWire busses and plugging them into each other causing the possibility of a failed bus bandwidth reservation, thus causing an audio glitch... or horribly complex networks with circular paths built into the topology causing additional bus bandwidth constraints due to the overhead of the spanning tree protocol---but I can also say with confidence that they're all things that nobody on this board is likely to ever encounter....
Of couse, with any current standard other than FireWire (that I'm aware of), you can't even do the things that cause FireWire to fall over, so if you think FireWire sucks, you're truly clueless. It is an amazing bus even by modern standards, and when you consider how old it is, it is positively breathtaking.
