With snooker I think the boom is just local to China rather than the whole of Asia, but according to this article there are 300,000 snooker clubs in China and there are apparently 50-60 million snooker players in China:
A new snooker league has launched in China as the country bids to 'move from a major billiards nation to a leading powerhouse.'
metro.co.uk
Last years world championship final was viewed by 25 million on Chinese TV and more people watched it online (424 million streams, though that figure is for whole tournament, not just the final)
The Official Website of World Snooker
www.wst.tv
Think Matchroom started organising tournaments in China hoping it would become a new market, then Ding Junhui emerged as an elite player which helped grow the sport more. And it's just mushroomed in popularity from there.
The irony being that snooker halls are becoming rarer and rarer in the UK, and there aren't as many good players emerging from the UK. Ronnie O'Sullivan is probably the only snooker player that's actually a well known name to the general public. So it is a bit worrying what will happen to the game after he retires (he's already playing in a lot less events). Though they are bringing back a popular game show involving snooker to tv, so maybe that will help it get a bit more mainstream.
Just noticed after saying that the snooker boom is just in China and not the rest of Asia, that when you look at the womens world rankings there are quite a lot of women from Thailand doing well:
View the latest rankings via WPBSA SnookerScores. The WWS world rankings operate on a rolling two-year basis. Learn more by reading our Rankings FAQ. We [...]
www.womenssnooker.com
Number one player is from Hong Kong and I wonder if that formerly being a British colony has left a snooker culture there. I know a lot of African countries play English pool rather than American pool which I'm pretty sure must be down to colonisation.