Firewire comes in 1394a (400 megabits/sec) and 1394b (800 megabits/sec).
I suppose some might perceive that 1394b has more market penetration
on Macintosh systems, than on PCs, but I have seen the odd PC motherboard
that sported a 1394b port. You can also get add-in cards with 1394b.

SATA = 150MB/sec or 300MB/sec, and actual transfers would be platter limited

Firewire = 50MB/sec or 100MB/sec, and actual transfers will be less

USB2 = 60MB/sec theoretical, but practical rates are around 30MB/sec
       for enclosures.

Some Firewire 800 benchmarks.

http://www.barefeats.com/note01.html

Various ports compared on Macs.

http://www.barefeats.com/hard70.html

1394a here, is able to do more than USB2.

http://www.tomshardware.com/de/Vergleich-Externe-Festplatten-eSATA,testberichte-
239800-11.html

Where 1394a sometimes falls down, is when drives are daisy chained. (I
used to own two 1394a enclosures and noticed this in testing. There is
a difference between putting a chain of two drives, versus connecting
each drive directly to the computer. The packets are "store and forward",
through the chip inside the drive #1 enclosure.)

   computer ----- drive #1 ------ drive #2   (drive #2 is slower, like 20MB/sec)

   computer ----- drive #1     (a better config)
            ----- drive #2

HTH,
   Paul

On paper 1394a doesn't seem as fast but in practice it is
often faster than USB2, on PCs as well as MACs.