Can't you get a D80 + 18-135 kit lens for that price?
Nope...i don't think so. I just got my 2nd hand D80 and my knowledge on the recent prices tells me that a brand new D80 + 18-135mm lens is at least $1800+. 2nd hand D80 kit will be around 1600++ for a good deal, if not around 1700.
I would definately go for the Sony A100 twin kit !
1) Image stabilizer built in.
2) Spot metering (400D hasn't)
3) Better made kit lens.
4) The feel is better (than 400D).
5) Far greater number of shots per battery charge.
6) Carl Zeis lens ability.
7) Can rapid shoot longer.
Just my view