I just received an IR Extender which allows me to operate my 8300HD PVR that is located inside my entertainment unit. The extender cable plugs into the USB port of the PVR which much to my joy, is active! It works great.
SA will not accept Canaidian orders. I had some one bring it in direct since Rogers hasn't the smarts to offer it to their clients. My only concern at the time was if the USB port was active. A great deal at $19.95 :) US.

Can you download a video file to an external drive or a computer via the USB connection?

No.
You can't copy it via firewire either, in case you ask.

See "57's" great FAQ.

Just in case anyone finds this older thread I thought I would add that the USB port is only to power the IR module. It sends nor receives any data over the USB port.

Someone once mentioned that if you plug in a numeric keypad (those small ones for laptops) you could use it to change channels.

I've never tested this, nor can confirm it, though.

Yes that is right you can change the channel with an appropriate USB device. Just in case there was some confusion I was only referring to the IR module.

I use the usb port on my cable box to power my usb flashlight. that way It will give me enough light to shine down on my DVD player so i can easily see the power, eject and play buttons at night time. comes in handy too. since I didnt feel like getting a DJ lamp cus those would get too hot and bright.