64 players are of course awesome but will all good there is some hurting also. I can assure you that the 24 player limit is not about us being lazy but the experience of a massive battlefield is not bound to the amount of players! And as many of you remember most clan wars where player with 8vs8 or 12vs12 and what we have seen many of the 64-player servers are mostly half-full or having lack of performance.
We have made it sure that Battlefield 1943 will feel big and have a fast pacing, bf1942 actually had very low pacing! If you place 100 people in one room it feels very small, but if you put 100 people on the streets it seems like nothing! 24 players will give us the benefit of having full servers almost all the time and the whole map area is being used!
Beside these design decisions there are technical limitations. There are very restricted bandwidth limits on the consoles and we are networking a lot more then 24 players:
24 players are networked
Almost as many physics driven vehicles with movable and destroyable parts
All destruction, if a wall is being destroyed on one client we need to update it on all the others, otherwise we could end up with players hiding behind non-existent walls. If we did remove all destruction and all our vehicles we could have more players. But no other game gives you the wide gaming experience we have!