It's Thursday, so it's time again for another update on what's new on the PlayStation Store. Sony's offering a nice deal on some PSN-only games this week, with seven different PSN titles getting half off the price until next week's update. The usual round of add-ons also make an appearance, most notably the Ghostbusters costumes for LittleBigPlanet. PSP owners, on the other hand, get a trio of downloadable games and some add-ons for Rock Band: Unplugged.