FWIW, I'll throw in my data point here.

I ran as-delivered 1.02 consumer image on my new 60GB Mk2a for quite a while. No funny behavior.

I changed to 2.0b11developer + Hijack 2.96 the day beta 11 was released. I have tended to leave it running 24x7 on AC power playing a shuffle of my top-level playlist to see how things go..

I did get some fail-to-reboot-after-synch errors previously reported here, but it always came back. I've left the clock visual running in case of lock-ups. It locked last night while I was asleep and only unlocked when I power-cycled it ~6 hours later.

Doug is your non-Hijack control subject, I see. if you need another I'd be willing to back Hijack out (I haven't really exercised it yet, anyway).

(Odd, probably unrelated oddity: Emplode was finding my player just fine with broadcasts, but it won't now unless I change to the specific player address)