I found this guy's youtube videos during the course of my usual Internet wanderings.

He does interesting, if somewhat provocative, videos on second language learning.   I'm not sure I agree with him across the board on everything.  (He sometimes comes across as a bit cranky and impatient of other views).  But I think here at least he makes a good case for why second language learning is best done through input that the learner is genuinely interested in.

After hearing this, it reinforced my committed to the value of comprehensible input and showing movies in class.