It says the episode title of the next episode in the previews at the end of all the episodes, so why would you not allow people to post them?
I'm quite sure alot of people don't watch the next episode preview, not wanting to be spoiled. Plus, sometimes, in fact often times, the episode titles go more than one week in advance. I think it's ok to continue posting episode titles, as long as the people going to the ep title thread know they might see slight spoilers.

I have no idea what the official gotwoot stance is on this.