Originally Posted by chillywilly 
I wonder what kind of noticeable difference would be between a Class 4 and a Class 6 SDHC card?
About 2MB/s...
Seriously, I have't had a chance to do a head to head comparison, but I remember hearing and reading about people complaining of "stuttering" with music and video when the class 2 miniSDHC cards first came out. I imagine the transfer rate differences would be very noticeable when doing large file transfers, also.