This is gonna sound weird, but with the deaths of Philip Seymour Hoffman and Maximillian Schell in the past few days, I bet all the IMDB scores are skewed this week. The fact that Jason's score didn't move much may very well be a sign of how much buzz he got this week. It just got overwhelmed by other buzz.
Good point, Alle. Actually, though, this score reflects IMDb searches through mid-yesterday. We won't see the effect of Philip Seymour Hoffman's death (or Maximilian Schell's, for that matter) until next Monday. This week his number went down, because the reaction to his passing didn't come until after the calculation had been made.