I went to the website for the Ministry of Foreign Affairs for Thailand to look for the current visa requirements. This is the page I found:
these requirements appear to be the same as the pre-coup requirements. can soeone confirm or deny this?
A friend of mine flew into BKK 2 weeks ago. He e-mailed that Thai Imm. did not check to see if he had a return air ticket. That is the same as all my previous trips. They never look for an onward ticket.
The way I understand the new visa rules, a person can only spend 90 days out of 6 months in Thailand without getting a visa from a Thai embassy in another country. The new rule was designed to stop long stayers from just doing border runs and getting the free, 30 day entry permit. Some have stayed for years without ever applying for a visa. This was aimed at those using the land border entry points, not visitors flying in.
I hope this helps.