Just came back from my turkey trip. Have been using D80 since 2006 and is very happy with it. My tour group got one guy who is using the D300. That is his ver first camera and we started sparring with each other using our camera. IMO, D300 produce very good photos compared to D80 and is much faster too...
Sad to say, till now, I have yet finished exploring all the functions on my D80. Learnt more functions through this trip have also been slowly poisoned by the impressive features of the D300 especially at high ISO.
Well, I will "try" to stick to my D80 till I fully explore all the options that can assist me to shoot great photos. Maybe the next change is the rumoured D400

hehehee
For those who r getting their first DSLR, I would recommand D300 anytime. I paid 3k for my D80 with 18-200 vr lens so I think the current price of D300 and 18-200 vr is very worth it.
my 2 cents.
Cheers
Francis