Subtitles now default to the generic white blocky type. The same settings in 1.52.1 display the stylized subs fine. I'm not too technical, but looking at changelog it seems 1.53.0 has a new mplayer build and perhaps that has something to do with it.
Here's a screenshot of the settings that work in 1.52.1 but not in 1.53.0:
late 2006 iMac 2.16ghz Core 2 Duo w/3gb RAM
Airport Extreme->ethernet cable->PS3
Transcoding w/ MEncoder
Thanks in advance for any help.