I recently noticed that for a couple of conferences almost all talks had a five-star rating. This lead me to question the way rating talks currently works.
We could be to get rid of the star rating for a talk altogether. As a speaker, I do not really care about the stars but in fact am more interested in the comments.
We could allow users to up-vote / down-vote comments and display them sorted accordingly. This is independent of whether or not the star rating for the talks stays or goes.