USB3 is here now - its already out there on new high end PC's, and will be on Apple's new MacPro's in Q1 next year.
so... we can be both fast and universal.
I agree, yet if S3200 (protocol/standard already launched in 2007) goes forth according to schedule, it will again outperform USB at just about the same time as USB 3.0 reaches market for mid level computers. The advantages of Firewire are:
1. Less CPU intensive. Firewire is peer-to-peer and USB is master/slave, where Firewire demands little or nothing from the CPU, USB transfer rates decline as CPU usage goes up.
2. Firewire delivers more power over the cable. This is of particular interest to MFDB shooters as well as Live View users who go through a lot of batteries if their backs can't run of the computers power.
3. Firewire supports considerably longer cable lengths than USB. USB 3.0 is rumored to increase the possible cable length, but then again Firewire also gets better by every iteration and should keep in the lead as it has done since the first protocol release.
4. Firewire has up untili now been more sturdy in its build, due to manufacturers opting for fragile mini-USB plugs whereas firewire implementations mostly uses the larger standard connectors in MFDB's (videocams aside...)