Question, it's a simple one, I think...

[FEJ]

Yes, you just wont get the same speeds as USB2.

if you have USB2 inputs on your computer, and a USB2 device, make sure you have a USB2 cable also. (if you dont, it wills till transfer at USB 1 rates)

There my be a few exceptions where it's not backwards compatible, but I havent run into any yet.