I have a BTO 2011 27" iMac spec'd to the max. I am also running Lion. I have a few USB 2.0 thumb drives that I use every so often and needed to use recently. I plugged one into the USB port on my Apple Keyboard with Numeric Keypad and noticed that it was slow to write to. After noticing this, I then plugged the thumb drive directly to one of the USB ports in the back of the iMac and noticed that it was just as slow. At this point, I thought that it was just that particular thumb drive and tried one of the others and found that both are equally slow. Both of the drives were formatted on my old Mac years ago, a PPC G4 Mac to be precise. One drive was specifically formatted for OS X and the other using the Windows/everything else format. I don't want to reformat the thumb drives just yet as I have another issue with them, files not being seen by both my iMac and my old Mac. Am I to assume that the only fix to this issue would be to backup my data and completely format all of my thumb drives using the iMac or is there something else I'm missing?