My responses are based on the version of GPE that I installed on my Zaurus. But, based on what I saw when I installed the suite on my N800, the apps seem to be the same.

1) Yes and yes.
2) Very poor.
3) Qualified yes. I have synced GPE with the Linux version of ... (I'm drawing a blank right now). It worked, but there were some issues I never was able to get fixed with the Zaurus.

I am also a Palm TX user and I'd really like it if the N800 did it. But the PIM apps simply aren't good enough for me to make the jump.

Besides GPE PIM, there is pimlico as well. I am a long time user of Palm and my current device is Sony Clie. I currently carry both, N800 and Clie, with me. I have not found a good way to transfer my contacts and calendar info from Clie to GPE PIM or Pimlico on N800. There might be a way to do it with gpesync and gnome-pilot (on Linux) but I have not spent any time on it to figure out how.

I think the appropriate response to the OP's question is now:
Yes, you can replace your Palm TX if you are willing to use beta software to emulate it.

(-:

[calador]

Great input, thanks. Much food food for thought.
I have a TX and Treo650 and frankly I find the screen size of the N800 much more usable for extended periods, like a full work day.
The Treo screen at 320x320 is just too tiny to truly work at all day, notably with calendar and emails. The TX is a nice hand size, fits so easily in a pocket, but the N800's screen wins the day for me. I viewed a movie the other night, with the scenes situated in Fiji, at highest resolution and I swear you could lick the tropical leaves in the foreground! lol

With dual SDHC potential, pretty decent handwriting rec, real radio and the camera for video potential is indeed there, I think these excellent tablets just need some development time. Is it even a year yet?
Maybe attract a few more of those savy Palm programmers finding new code to surf.
wink wink nudge nudge eh!

i'm planning to use a combination of my n800 and a slim new mobile phone to replace my treo 650. i like the fact that i can continue to use some of my favourite palm apps and games while using a powerful linux mobile device. the perfect marriage for me!