Yes, the HyperSynch technology was reallllly looking like it would be promising a year ago, but then after the actual shipping of the transmitters and receivers, it was discovered that the Canon 580 and 580 EX-II flash units had some pretty serious radio frequency interference issues that varied from country to country, or batch to batch, and one of the muckey-mucks at the PocketWizard firm lamented publicly that they had purchased one,large batch of Canon flashes with which to do their development; he stated that he wished they had bought them all piecemeal off of e-Bay, to have received a broader cross-section of the actual flashes on the actual market. So, this was really an unfortunate case of a revolutionary new technology, HyperSync, that was almost totally killed off by this unforseen Radio Frequency Interference issue that just took center stage, and PocketWizard went into sort of a self-protection mode, and developed the shrouds and stuff, and basically, this discovery also killed what was SUPPOSED to have been a prompt roll-out of the HyperSync stuff for Nikon flash equipment.
I was not too aware of your use of E-TTL flash. I have a 5D and 20D 580 EX-II flash and eight or nine lenses, and have used the 580-II in E-TTL mode, and am aware of the odd inconsistencies in Canon's flash metering with that flash and those two cameras. Drawing comparisons between Canon and Nikon often gets me into trouble, but honestly, I think the color-blind Canon bodies (all of them except the newest 1D series models and the 7D and 60D-era cameras) simply do not have enough information to make the right metering choices in AUTO modes, the way the Nikon bodies do with their 3D color matrix metering and color-aware flash meter sensing...but you and I are not the only ones to complain about Canon's E-TTL flash metering performance...it's one of the company's weaker areas, IMHO. And NO, the issue of direct flash metering being "okay" versus bounce flash being "stupid" is not only your problem--it is CANON'S problem. The problem rests with the equipment, and not with you.
Kinda' sad for PocketWizard to have bought a whole batch of fairly low-RFI Canon flashes, and developed their hardware, marketed it, and then released it, and then discovered that the RFI levels of various Canon flash units was all over the map, depending on various factors. If they had done more widespread testing, or testing on units from around the globe, I think right now we'd hear a LOT about the HyperSync technology, but the rollout and then immediate misfires and the huge problem with RFI was a dealbreaker.