Ahhh, and thus Jude finds out the difference between how long a tourist VISA is valid for <- which is 3 months from the date it's issued :)
AND
how long you get stamped IN to the country on a tourist visa <- which is 60 days ;)
This topic comes up quite a lot so I hope the person doesn't mind me using it as an example..
I will close commenting though this is a teaching post only. remember people knowledge is power.. :P .
TLDR : Answer Summary
The post clarifies the distinction between the overall validity of a tourist visa in Thailand, which is 3 months from the date of issuance, and the duration one is allowed to stay in the country, which is typically 60 days after being stamped in.