We're looking at 1080p resolution at 60fps in both single and multi-player, a 4x detail increase to texture maps and a 2x resolution boost to shadow maps. Texture streaming is no longer required owing to the PS4's prodigious RAM, and there's longer draw distances, better LOD and improved particle effects.
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It's important to point out that this is a remaster, not a remake. Where existing higher quality assets are available (for example, cut-scene character models) they are utilised, but there's little evidence to suggest that Naughty Dog has upgraded any of the environments, or boosted geometry. [...] Geometry quality is unimpressive, environment detail is relatively spartan and this section does little to showcase the game at its best.
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It's also apparent that there's still a yawning chasm between the quality of the pre-rendered cinematics - almost certainly rendered at a much higher resolution, then downscaled - and the game itself, resulting in a jarring leap between FMV and gameplay not helped by a small pause between them.
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To answer the question everyone's been asking, frame-rate isn't locked to 60fps, but The Last of Us Remastered does spend the vast majority of its time at the optimal refresh. [...] The first confrontation with a fungus-spewing Bloater sees frame-rate hit a minimum of 48fps.
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At this point it has to be said that the game's day one patch was not available for testing, so there remains the possibility that things may improve once that hits - and we'll be sure to update you if that is the case.