Among other things, it would make it easier for the remaining countries on the candidate list - Turkey and Macedonia for starters, in a later stadium perhaps Serbia, Bosnia and other Balkan countries - to join. It would also reduce the amount of domains on which all countries (27 now, probably 29 soon with Iceland and Croatia, then possibly more still) have to agree for it to be passed, as unanimity becomes increasingly difficult to reach as more countries join and as the member states become less homogeneous in terms of culture and economic situation.