I was surprised by the result because I read several polls suggesting that the new constitution would be approved by at least 70% of the vote. But the unofficial results are 56.7% voted yes and 41.3% no.
I made this map and it looks strikingly similar to the 2006 legislative election: the poor Northeast, the stronghold of the former prime-minister Thaksin Shinawatra, voted against the constitution.
Detailed results
http://www.electoralgeography.com/en/countries/t/thailand/2007-constitutional-referendum-thailand.html
