I know this may not help a lot, and definitely not yet, but Pocket PC's (Windows Mobile devices) don't have any restriction on the number of categories, allow more than one category per item, and sync beautifully with the Mac using the Missing Sync.

The problem for you is that there are not too many non-converged ones around now, and you won't be able to sync with NUDC, though you will be able to with NightHawk when it's out.

If Palms are going the way of the iPhone, then I'd guess the improvements would be UI based, not functionality. From what I've seen the iPhone is a very weak PDA (it has zero categories for example!), though of course that doesn't mean Palms will be as bad.

If you choose not to decide, you still have made a choice