Don't let the price (£3.99 at time of purchase) put you off, you'll simply not find a better value card reader than this.
As with most card reader plug it in and you end up with 4 extra drive letters under My Computer (using XP or 2k). The speed of the thing tho is the most impressive, it really is quick and has no problems copying or moving hordes of photos. My two previous "usb2" card readers are dinosaurs compared with this.
Huge bonus points for supporting the new SDHC cards as well. My Class 4 SDHC card works perfectly, also tried it with standard SD, MS Pro and MMC as well.
Bottom line buy it, it's really quick and supports a stupid number of card formats :).