the idea where films have to make so much in their opening weekend to cover the their opening costs, even when the 2 amounts DO NOT equal the same, is very much like the back catalogue of the music industry.
So if it cost them $200million to make, and they say they need to recoup $50 million in its opening weekend, then its not unreasonable that they expect it to claw back that extra $150mil both worldwide, on dvd, and ultimately when it ends up in the bargain bucket next year for $7 when you buy anything else in store.
On topic, Tron never interested me, not in the slightest. I saw the trailer for this in 3D, i couldn't help but think that this could easily beat avatar and so i am looking forward to seeing it. Before some fanboy tries to jump on me from across the web, what i mean by beat avatar. Is actually do something other than produce a load of excellently rendered special effects. Like i don't know, have a storyline which isn't obvious within the first 15minutes (and thats for slow people)