I have read alot on this board in ref to trying to get the SV-AV100 to go above the 2GB card capacity.  I even tried getting a Sandisk 4GB SDHC card and formatting it correctly to Fat16 with not good results.  I returned the card. I realized that I was trying to get the camera to use this higher capacity card so that I could get more recording time out of the camera.  I then thought to myself, why do this?  I was able to purchase 2GB cards locally for about 10 to12 bucks.  That was local. You can find them online for about 7 bucks. The 2GB cards give you an mpeg2 recording time of about 44 minutes. When I go on a trip I never seem to fill a 2GB card but if I do, I have another card available.
If we look at the cost of these cards when when I bought this camera in 2003, they are a fraction of what they were. I think that these cards will be available for many years to come as there are many devices (cameras, PDA's and other devices) that only have the 2GB capacity.   
This camera is still my favorite camera and I love the way it sets up to be a video player so you can go over your footage.  Really neat stuff! Enjoy!