Even if it was a title, episode titles are by definition not spoilers.
Well.... yes & no. It depends on when the information is officially released, I should think. Case in point from B5. There is an episode from the end of season 5 which one could consider a big spoiler. At the time, the episode titles had been picked up through subterfuge or similar act and then posted & divulged on the Net. Given that it was not by the studio or the series creators, I can easily see why someone would consider that a big spoiler. However, once it had been done officially, whether by Warner Bros or JMS or TNT then all bets are off. There's only so much you can do.