Bad support
I have been using PalmOS since IIIx came out, my last PalmOS device was a Treo 650.
Recently I had to ditch it, and went for a slim, light and hassle-free LG dumbphone, accompanied with a PPC PDA(no phone) brick which has bluetooth, wifi and a keyboard which I could carry around or leave at home as needed. Yes, so I joined the dark side. PPC interface is a bit painful after the fast and clean PalmOS UI, but it works. Since it is not my phone, the interaction speed (number of taps/button presses to do something) is not important anymore. And now I can browse with Opera Mobile while downloading mail in the background, and have a PIM app open in the background.
Reasons? I now use a x64 Windows system, for which Palm still has not released a simple USB driver for hotsync. Lack of multitasking was getting to me. There was no wifi, and no plans for one. And frankly all the workarounds for SDcard access, decent call volume etc were getting to me. Occasional resets were annoying too.
If and when Palm releases a new version of its OS I may reconsider (and I expect by that time the Android etc may be a better choice). Until then I am taking my business elsewhere.