Exactly!
I especially want to see a 1-50 system and if that angers the reach fans, there is always the Reach system (which has been confirmed) for them too. Having the EXP from halo 3 and not the 1-50 system, then saying 'We are mixing Reach and 3' is just teasing the players who loved halo 3 ranked games.
My opinion is that if Halo 4 is essentially the same system as Reach, 343 will be slaughtered on youtube comments and general opinions on forums.