I've been back to Pattaya for 3 weeks. I am not finding that service has improved.
Yesterday was another good example - small restaurant with foreign owner. Thai server walks to my table and glares, until I order. Not one word spoken. Great food by the way, and I did receive "service", just not what I wanted or expected.
Some of my friends have complained the same thing, making the comment that staff do not want to be too nice, because more foreigners might come and they will need to work harder. It is tongue-in-cheek of course, but it shows that the problem exists.
It is no longer the land of smiles (at least, not in tourist areas); and now that 2 years has passed, the people who wanted to come to Thailand may have lost interest.
I will say the tour busses aren't missed.