EA showcased its new ignite engine for FIFA 14 at E3 2013, the new engine aims to add better atmosphere with real crowd reactions, better player movements and is capable of making four time the calculations of EA's current-gen engine it uses for the FIFA games. The one thing that stands out for me is the engine being able to think better i.e essentially the AI being smarter on/off the ball, even though these changes are exclusive to the PS4 and Xbox One we're getting closer to an authentic FIFA sim. EA has confirmed that PC gamers will not be getting a taste of the Ignite Engine this year.
Barcelona takes on Athletico Madrid in this off-screen gameplay video of FIFA 14 from E3 2013's show floor.
Current-gen gamers aren't being ignored by EA as they'll be getting a bunch of new improved features, one of them includes better protection of the ball which was at display in the gameplay video, but the player wasn't able to pull it off that well–losing the ball near his own penalty area, whether the AI will be this creative is yet to be seen as the video only shows 1v1 gameplay. The game doesn't look much different from FIFA 13 in terms of graphics as EA seems to have peaked when it comes to current-gen graphics.
The exisiting current-gen fanbase will not feel left out in the early months of the release because next-gen versions of FIFA 14 will be released a good 6-8 months after the release of FIFA 14 on the Xbox 360, PC and PS3.