Well, volume 1
http://www.amazon.co.uk/History-Hobb...0447367&sr=8-1 came out at the beginning of this month over here & I just finished it yesterday. Vol 2
http://www.amazon.co.uk/History-Hobb...0447367&sr=8-2 was supposed to be out next Tuesday, but according to Rateliff's blog he only just completed the Index on Sunday & he's been given a pubilcation date of the 18th of this month.
TI suspect that the edition you link to is the slipcased set of both volumes & the 70th anniversary hardback of TH.
The first volume is interesting (actually the bulk of vols 1&2 is the original manuscript/typescript of TH, but vol 2 will contain the attempted re-write in the style of LotR which Tolkien began in the early sixties).