I remember reading from somewhere that they use tile based deferred in BF4. This is why they can also support quite efficient MSAA. However even 2xMSAA still drops their frame rate down by a big factor (20% to 30% depending on the GPU), making it practically only useful for the ultra high end PC GPUs. Most players prefer to improve the frame rate first to stable 60 fps and then resolution to the display native (1080p / 1200p / 1440p) before upgrading the AA quality.And if memory serves, BF4 doesn't use the tiled based method
Multiple samples per pixel are still very important in the future. I don't deny that. Post AA gets you only so far. However post AA has become more important than MSAA on PC, because it is practically free, and thus allows much higher percentage of PC players to play with anti-aliasing. MSAA certainly is nice for those people that have monster GPUs and like to play with ultra-settings. However even 2xMSAA is much more (almost 10x more) expensive than SMAA for example, and often looks worse (doesn't hide enough aliasing). To make it look good enough you either need 4xMSAA (super expensive) or need to integrate the extra MSAA subsamples to your post AA filter. SMAA S2x does the latter and looks quite good.I understand that dedicating extra resources to one aspect of a pc port may not be a practical business decision. That's fine, just say that! However, I'm not willing to give a free pass on msaa just because an engine is deferred.
There are also ways to improve AA filters further by using the coverage sampling hardware in modern GPUs. However the current PC graphics APIs (except for Mantle) don't allow us to access the coverage sampling data structures, so these methods would mostly benefit the consoles.