My guess would be if you buy it before December then it's not genuine, or an unsupported beta version.
According to other posts Nokia appear to have recalled the few that were sent out as demo version to make changes.
I use ebay frequently and would not risk buying one from there or a similar non retail supplier until stock is seen in shops or @expansys.
Whether prototypes/pre-release phones or final, shipping phones, they'd still all be "genuine" (or at least I don't think any other company is doing "pirate" or "clone" 9500's anyway).