I got one of these about three months ago and have been using it daily ever since.
The main reason I opted for one of these is the quality and brightness of the screen, it is by far the sharpest one I have seen.
I also wanted the features of pocketpc2002 and at least 64meg of ram.
The 3970 has 64 meg ram, 48 meg rom of which 16 meg is available for storage.
It comes with bluetooth built in which I have been using with a GPRS account on a Sony Ericcson moby.
This works very well - I use it very frequently for realtime stock quotes, emails etc, get good fast access.
The battery life could be better...and as with other ipaqs there is no way of replacing the battery.
It has an SDIO slot so there is opportunity for expansion.
But it does not have a built in CF slot. The other main contender for my money was the Fujitsu Siemens Loox - the reason I chose hte IPAQ was the quality of the screen.
Handheld - 64 MB RAM - Screen: 3.5 in inch - Display: TFT active matrix - CPU: XScale PXA310 - Bluetooth, Wi-Fi, Wi-Fi - Microsoft Windows Mobile 6.0, Microsoft Windows Mobile 6.0 Classic
Handheld - 64 MB RAM - Screen: 3.5 in inch - Display: TFT active matrix - CPU: XScale PXA270 - Wi-Fi, Bluetooth, Infrared - Microsoft Windows Mobile 5.0 Premium Edition
Handheld - 128 MB RAM - Screen: 4 in inch - Display: TFT active matrix - CPU: XScale PXA310 - Wi-Fi, Bluetooth, Wi-Fi - Microsoft Windows Mobile 6.0, Microsoft Windows Mobile 6.0 Classic