There are just 17m in the global index; I would have thought that it would be possible to get that many in just the UK.
Seems to be based in part on the Dmoz float with some IP based website>country pairing. All IPs for the country sites point back to the same UK IP. Still though it is very light on the UK index. Some of the SERPs seem a bit dated as if the SE was on its first spider run. Still it is a rather ambitious undertaking. Though the fact that it has to issue a press release to attain some form of prominence is worrying.