I was at WDW this past week and did "Stitch's Great Escape" twice at busy times of the day. I've done it before, and don't really like it but do it anyway.
I would hesitate to say the theater was 25-MAYBE 30% full both times. The park was pretty busy and Monsters Inc, TTA (rode it and saw Space Mountain with the lights on!), CoP all had more interest than this. Heck, those Country Bears, as primitive as they may seem were almost packed. How much longer does Disney plan to keep this going? It's a horrible attraction anyway. Alien Encounter wasn't great but was better. Maybe I'm missing something, but I fail to see how they can justify keeping such an un-popular attraction open. Nobody really seemed impressed by it. The theater is really interesting though -- but the 'harness' things hurt both mine and my mom's shoulders (we aren't large people) and the seating is uncomfortable.
Disney needs to drop this. I can't see them keeping it forever.