I believe in 2002, 512MB was the maximum capacity of an SD Card. I'm a first-timer to MP3 players and just purchased a Coby from the local supermarket. For a relatively cheap device, this is working out grand for me right now. However, the 256MB is slightly limiting, and the manual states that 512MB is the maximum expandability. Should I take that as a literal limit, or might new technology allow me to toss a 4GB SD Card into this thing? I ask because I know very little about SD Cards. Thanks!