Rosseau,
I can upload pix to my cards via a cheap card reader. I use a $15 SanDisk for my compact flash media. It is basically identified as another drive whether you use a Mac or a PC.
On my Mac, I use the "export" function. On my PC, I use the "save as" function. You just have to specify where to send it. For example, when I've got a Lexar card in the reader, it shows up on my desktop as "Lexar Media". On some PC's you can give the card reader a "letter" designation as you would your other drives.
HTH,
Luis