What it is: Why, it's a PS3 game ported to PS4! Make that three of them, three excellent PS3 action-adventure games, Uncharted 1-3 (just the singleplayer), ported by development studio Bluepoint, coming out in lieu of the delayed-out-of-2015 Uncharted 4 on October 9.
What's been changed: I saw it at a PlayStation demo event yesterday, I played it, and I'd tell you that it looked like the PS3 games running on the PS4. Bear in mind that these are three of the best-looking, best-playing PS3 games, all Indiana Jones-esque climbing and shooting adventures set in exotic places around the world. Without benefit of the game running on PS3 right next to it, I can't easily spot the difference between the ports and the originals, but Sony is talking about it being 1080p, 60 frames per second, says it uses the better character models from the game's cinema scenes in its gameplay sequences, has better lighting, better shadows, improved draw distance.
Less motion control: Did you play the first Uncharted? Did you enjoy when you had to use the motion sensor in the PS3 controller to keep hero Nathan Drake balanced as he walked across a log? If your answer is yes, you're weird. If no, well, you might be happy to know that motion control for log-crossing has been excised from this collection, according to a rep for the game's original development studio, Naughty Dog. They are leaving a motion control option (not mandatory) for tossing grenades.
Difficulty tweaks: The new game will not have dynamic difficulty, which they're saying will be coupled with some balancing tweaks to make the game flow better. I asked specifically about whether enemies in the first Uncharted wouldn't be bullet sponges anymore. I got a general affirmative that damage to and from enemies is being recalculated across the games. Bluepoint is also working on a special "brutal" (not final name) difficulty level that is designed to be challenging even for the game's most skilled testers.
We played it... briefly. Just the building collapse sequence from Uncharted 2. It seemed faithful. There isn't anything to the collection that seems like it will merit a replay for people who were satisfied playing the games on PS3 -- they're trying to hook some of those people by offering voucher for a forthcoming Uncharted 4 multiplayer beta -- but for newcomers, the collection should be fun. Those Uncharted games are really good.