I've preordered too. - But some fans will not buy/support the concert but they will see it anyway - and enjoy it.
On the other hand I do understand why some do not want to support the idea of SONY releasing poor MJ material. - They want to make a statement to SONY that they need to release good quality. "MJ fans will not buy everything with MJ's name on it if they quality is not good!"
It's a difficult matter. - I am just one of them supporting the release and hope it sells well - that will maybe make them release more concerts!
If Wembley DVD sells poor - why would they release another concert? They are a buisness, not a charity group formed to please MJ fans!