I would post this on EA's forum as feedback actually. I would like to see what people say and if you can pull an EA person in to get an answer for it. http://forum.ea.com/eaforum/categories/show/31.page
I think that if they are offering special unlocks for pre-order people then they aren't going to let every beta tester keep their plethora of unlocks that they gained. There is probably no way to NOT tee you off with this comment but look at it as...hey thanks for letting us see some of the game. To be honest, I was happy to that they even allowed the unlocking for the beta. The BF2 demo didn't allow any upgrades.