At the end of the day, you can't satisfy everyone. If they include WiFi but not Bluetooth, then Bluetooth fans will moan and vice versa. If they include both, the price goes even higher and people moan they only use one and managing several different models like the SL-6000 pushes up costs again.
I think Sharp are trying to do something a bit different again while keeping the device flexible and I applaud them for that. What they should do is include some nice plug'n play software for both WiFi and Bluetooth.
64MB of RAM is still double what the 5600 has so I'd be happy with that. Since I have a Bluetooth CF card and no WiFi stuff I'd be happy having a large internal hard drive too so I could always keep the Bluetooth card in the CF slot. SD cards tend to be too flakey or too slow for doing things like making voice recordings or playing videos, so I think this is the right way to go. If only I could justify the expenditure