FWIW, on another bid that I made for Paris, I actually started my bidding on the HK priceline site www.priceline.com.hk. I started at HK900, then 950 then 1000 and then I stopped. HK actually allows you to continue bidding without changing the location or star-value. The location I was bidding was 4-star Opera Quarter East Les Halles.

At that point I stopped, thinking that maybe the inventory in HK was different in this case (HKD1000 = USD 125). After that, I bid on priceline.com and bid up to $110. I received a counter offer of USD 129 and I accepted. It was for the Novotel Les Halles which is what I was expecting based on what I read on www.biddingfortravel.com.

However a few days later, my friend in HK did the same bid on priceline.com.hk and was successful bidding at HKD 1050 = USD 132. So looks like HK and US priceline do seem to share the same inventory.