USB2.0 has a theoretically higher bandwidth than 1394a (firewire 400). In practical usage that doesn't pan out even remotely because the fundamental difference is that USB 2.0 is not bi directional. Data cannot travel both ways at the same time. So reliable for more than four or eight simultaneous inputs is about as far as you get. Now, several companies have written better USB protocols like RME (Babyface, UFX, UC) but for critical projects firewire is the goto protocol-until you move into PCIe cards which win the race hands down for both latency and speed and stability.

Don't forget, there is USB 3.0 already about to replace USB 2.0. It is about 10 times faster ( 5 GBit/s ) and even a third quicker then eSATA connections.
FireWire is quite a bit slower... Still, I definetely prefer to avoid FW and USB, all together.

I haven't even heard of a USB3 interface in R&D let alone production. Hard drives? Yes. I've seen those. I think everyone skipped it for Thunderbolt.

Oh and eSATA over a SATA6 connection is pretty darn quick. Overall though, you're correct that USB3 is a vast improvement over it's predecessor.