I've seen this bike at Elite KTM in Loveland. I generally go there for stuff on my '09 450 XC-W. That bike is pretty clean, but I think a more reasonable price, like ~$3300 would be on the mark. Those guys generally negotiate or have you negotiate with the seller if its on consignment. I believe that bike has been there for a while.
For context, I paid $4200 for my 2009 with 120 hours and 2700 miles on it. I've had to change the jetting, added debris bars, added the optional factory fan, added a stop light switch, a front tire, and a Rekluse clutch. I've got about $6k into mine not including protective gear (~$3k). It runs great and is a helluva lot of fun!