Here's the thing about Battlefield 3, they should not be limited to 64 players, that has to be a design choice on the part of the devs.
Why?
Because Battlefield 2 could run 128 players as PR has shown
http://www.realitymod.com/forum/f10-pr- ... icial.html
It ran stable, people could fight each other just fine, but funny enough lots of things broke because the game was only designed to display 64 people so the game only displayed name tags for the first 64 people and only showed scores for the first 64 people and so on. But it was stabled, the server had a heavier load but even when crammed 128 people into the same 200 meter area firing and shooting at each other the game kept up. The server had a higher load but nothing crippling.
Second Aaron can be demonstrated as having console stockhome syndrome.
This is Battlefield, the more players the better, the more players the more targets AND the more equipment one gets.
One can not justify eight manned positions on the aircraft carrier if you have 24 people, no can one justify actually giving ships the correct amount of weapons. You can't justify things like AC-130 gunships manned and flown by the players with only 24 on the field. No can you justify more than a single helicopter. Dogfights in 24 player games are non-existence unless that's all the map is.
However since this is also battlefield the real question is about how friendly the engine is to modding. Most mods lost everything in the move from BF1942 to BF2 because the engines were radically different. If PR and FH2 can move lots of assets over to BF3 you might see some very interesting mods emerge.
Another console lack, and a major one in this case. You can get by over there on Call of Duty This years Sequel on the consoles because they've killed their mod community, but over at DICE they are still fans of mods in the base Battlefield games. Or have been to this point anyway.