Ooh, this is like the debate between Mac and PC and at the end of the day it comes down to which operating system you prefer.
For the Palm OS: small, elegant OS which generally means it doesn't eat as much battery power and - generally but not always now - the pdas are physically smaller. Also good for those who dislike the Microsoft hegemony in computing.
For the Pocket PC OS: easy-peasy interface with the PC, tends to ship with Pocket versions of Word and Excel which means you can edit documents and spreadsheets on the move.
I can think of more cons for the Pocket PC than the Palm, too: against the Pocket PC is that the OS functions like a cutdown version of Windows, with all that implies for cumbersome file systems - and boy, is it cumbersome in the Pocket iteration. Lots of drilling down through folder structures. More power-hungry, too: your battery won't last as long. I've had some issues with ActiveSync (which syncs the data between your PC and the handheld) crashing my main computer.
But ... lots of software available for both.
Do consider going for a wifi option - you think you don't need it now but you might be glad of it sometime.
If you need it for work stuff you might just find the Dell Axim running Pocket PC has the edge. I've used both OSs on various PDAs and my heart belongs to the Palm OS. Having said that, I've got an iPaq at the moment running Pocket PC and I do love the extra processing power you get.
I suggest you go to a retailer and play with both PDAs, or if they don't have the models you want, at least play with machines running the two different OSs and see which you prefer.