Comparing USB and SCSI is like comparing apples and oranges. Yes, you can do it but it's kind of missing the point.

for a USB-UPS self-perpetuating PC.

From what I have seen about future chipsets with USB 3.0 support, only a few of the ports will be USB 3 while the rest will be USB 2.0 so should not have any problem with compatibility with old devices. This is similar to some modern chipsets that still have so many USB 2.0 ports and a couple USB 1.1 ports. They are normally are different colour or on a separate connector internally off the motherboard and can be configured in the BIOS.

USB devices such as mice, keyboards, game controlers and inkjet printers work perfectly fine with USB 1.1 and don't even need the bandwidth of USB 2.0 let alone USB 3.0.
What'll happen if USB 3.0 doesn't provide USB 1.1 compatibility for these devices.

JonB hit it right.

And USB 3.0 should be plenty fast enough for all my external hd work.
Backwards compatibility is more or less an excuse for lazy people. If you can't figure out or don't know what USB version your computer came with then that's a user problem not a hardware problem. Aside from you being able to easily test if your device is compatible or not, I don't see what all the fuss is about. If you're going to upgrade to a 3.0 PC by the end of the year don't you think it's time you upgrade all those 1.x devices as well.

USB 3.0 will provide a much faster (theoretically) data transfer than any current standard, with the exception of 10Gbit Ethernet, fiber, and maybe coax, with a simple 4-pin connector. What more can you ask? Even SAS doesn't have that kind of bandwidth. And with most computers today having internal USB routers, thus providing many USB ports, there's little functional difference between USB and Firewire interfaces to the layperson.

Granted, even 3.0 can't provide the kind of juice that Firewire can, but the new standard provides almost double the power as 2.0, so it's at least better.

In terms of Intel trying to price Apple out of the market... Apple did that to themselves. The standard for USB actually came out before IEEE1394, and Apple made the (somewhat incorrect) assumption that people were going to be willing to pay for the dramatically increased bandwidth and power. Unfortunately, there weren't that many devices that could make use of that at the time... digital cameras were in their infancy and USB 1.1 provided more than enough bandwidth that the bottleneck was usually the memory chip speed, not the interface. So while Firewire was a bit more 'futureproof' in its versatility, it kind of overshot the mark.

Frankly, it makes no sense to worry about supporting USB 1.0-1.1 devices. Backwards compatibility can only go on for so long, and no one should be surprised if their decade-old peripheral doesn't work with a brand-new computer. Besides, consumer-level adoption won't even be for another year or more. As long as it works with 2.0, almost no one will notice, I'm sure.

The connectors are only the same from the outside. Some additional wire pairs are smartly hidden inside. Old devices should not notice but the new ones have some extra cupper to account for the bandwidth. This also makes the wires noticably thicker.

The popularity of USB has nothing to do with its reliability. Serial, parallel and SCSI ports were reliable. Nor has it anything to do with ease of use and simplicity. Firewire is just as "simple" and in fact is easier to use since it can utilize peer to peer connections obviating the need for proliferation of ugly USB routers which proliferate as USB, and since it is much easier to power up a device like a hard or optical drive, thereby eliminating the power cable.

So why is USB so wildly popular? Because it is the Yugo (or Trabant) of computer peripheral technology. It is cheap as chips to add and implement because the technology is simplistic and because Intel craftily chose to forgo high royalties in order to extend (and exterminate) competing connectors. Nothing more, nothing less. Give me Firewire or gigabit ethernet any day over USB for my heavy duty devices like external hard drives, optical drives, printers, scanners, and videocams. Give me Bluetooth for wireless goodness in my mini-periferals like mice, keyboards, speakers, and headphones.

My grandmother had a word for USB - "pshaw!"

i would rather have a better product that was not backwards compatible then a half baked one

First off, if they cannot guarantee compatibility with other devices that use the same plug (ie USB 1 or 1.1 devices), then I kinda think they should have used a new plug. I mean, I've got like 10 USB ports on my PC. If half were USB3-only, I'd be fine with that. It's better than not knowing if some device is going to work or not.

486-100 DX4
SCSI VLB Controller

Windows 3.1 screamed

Yes i do
My UMAX SCSI scanner still works fine
($600.00 dollar) from 15 years ago.
Always buy the good stuff