Quite frankly I think what will happen is much of what happened in GoF. We get a glimpse. There are a few parts of quidditch that help the plot along and work well for HBP. They can still give us WIOK, the R/Hr kiss, and a few other things without actually playing quidditch. But I think we will see parts. For instance the game in which Harry and the twins get knocked off the team (needed to see why the twins decide to leave and why Harry stops playing, plus it makes the audience hate Umbridge more), and part of a game to see why Ron doesn't go with Harry and Hermione with Hagrid.