I've read some of the above material now have gained just enough knowledge to get really confused.

Even my camera (a T2i) supports 'Hi-Speed' flash sync. I'm guessing that's what's referred to as FP sync in Atkin's overview. As the Rebels are not exactly top-of-the-line cameras I'm guessing almost all Canon's DSLRs support this feature. However, nowhere in the reviews of any of the flashes is this mentioned. I'm assuming the 580 supports it and likely the 430. How about the 320 or 270? I'm assuming the all-manual LumoPro flash referenced above does not support this. As someone who shoots mostly sports I could see the usefulness of this - especially at hockey matches where one can be a few feet from the players.

Also, there's no mention that any of the Canon Speedlites can be set to an optical trigger (to flash when hit with light). Is this the case? Obviously this could be overcome with a shoe adapter but this is disappointing. I guess Canon wants you to buy into the IR-based Speedlite communication.