With the official announcement of the PS4 and Microsoft's reveal of the next Xbox just around the corner, the true next generation is at hand. I personally feel that in terms of graphics, we won't see a dramatic leap from this generation's best looking games although there will definitely be a noticeable and undeniable improvement (unlike the Wii U's barely current-gen graphics).
In the gameplay department I don't foresee any meaningful changes, either. Any attempt to revolutionize gameplay will only result in throwaway gimmicks. What I do believe is that the next generation will be all about refinement. The next-gen will be defined by the raising of the bar across the board, from graphics, to gameplay, to user interface and everything in between.
Most importantly, the next-gen ought to replace old video game conventions with ones that either weren't previously possible or were simply too much trouble for the available hardware. Below are some very basic features that should become the new standard for the next decade.
Bodies that don't disappear- There's no greater immersion-breaker than seeing the carnage you caused vanish. We see the corpses remain only in a handful of games this generation such as the Halo and Assassin's Creed franchises, or Uncharted 2 and 3. Other games try to mask the vanishing act by having the bodies explode or disintegrate in style. We want to see the bodies pile up as the kill count rises.
More animations- We're still a good decade away from achieving Rango-like visuals but the increased processing power of the PS4 and the Xbox 720 should make room for thousands more animations that should virtually eliminate any awkwardness in movement. Uncharted 3's animations are the best of this generation but it should only be the starting point for the next-gen.
Recordable gameplay for playback- Savable replays are commonplace for some racing titles but non-existent for other genres. Only the Halo and Ninja Gaiden series this generation have had the cinema feature, which makes it possible to save gameplay data for playback and editing. This ought to be a standard feature for all next-gen titles as it has many practical applications.
Option to switch from first person to third person and vice versa- A few games have offered the option to play in first or third person perspective but one of the views is always nothing more than a barely functional afterthought. Most games will work in 3rd or 1st person and such games not only ought to give players the option to choose which perspective to play in, but offer quality and polish regardless of the view.
No more HUDs- Unless absolutely necessary, HUDs should be completely removed. This is especially true for fighting games and hack & slash titles that rely on a health bar. We need to get rid of the notion that life or consciousness can be measured in exact increments. Wounds, bruises and other injuries combined with subtle but noticeable changes in each character's animations and behavior should become the standard means of approximating your physical state and the enemy's.
No more orbs- Kratos, are you listening? The concept of refilling health/magic by means of glowing orbs is the single most arcadey video game devise that should've become extinct last decade. Surely, there's got to be a more natural way to visually convey the replenishing of one's health and powers than absorbing floating, glowing bubbles.