Here's a call to anyone who either:
A) has seen this problem
B) wants to see if they can recreate it.
I have a 64GB 3G+WiFi iPad, and I was delighted to find that the iPod feature on iPad allows for unlimited playlist creation, right on the device.
Now, I'm finding that when I create a playlist, it ends up disappearing at some point. I tried to narrow the cause down to certain circumstances, and I've found that it seems totally random! I thought it happened when I connected it to iTunes on my Mac, or my work PC, but I can't say it's constant. I'll reboot the Pad, connect to iTunes and it'll still be there.... then, I'll repeat that process and I find it missing!!
Why? I have both my machines set to MANUALLY manage music / vids, and I never am obliged to wipe my iPad if I try to add an album from either machine (the iPad is like the iPod Touch in this cross-machine friendlyness.. UNLIKE the iPhone).
I've noticed this can happen w/o any sync at ALL, to either machine, too.