I dont know how to describe Harry Potter And The Half-Blood Prince. It wasnt as bad as most people made it out to be. The visual effects were top-notch. the movie boasted a few hilarious moments, and contrary to what the critics felt, i quite enjoyed the romantic sub-plots. However, the main problem with the movie was that it never really took off. There werent any truly climactic moments and might even have come across as boring to non-HP fans. Essentially, i think the movie is just setting the stage for the final two installments of the series (which hopefully will have more oomph).
