Bloodborne gets performance upgrade by PS4 Pro users getting access to 'Boost Mode' early
Mobs are much smoother now.
As you can probably surmise, news of the PS4 Pro's upcoming feature, "Boost Mode" has generated some considerable excitement among the console's ownership (and envy among those who don't). PlayStation has been sending out Beta invites to various PS4 Pro owners to test out the mode, and users are reporting that games like Bloodborne, Rainbow Six: Siege, and The Witcher 3: Wild Hunt all see benefits from using the mode.
Of those games, Bloodborne appears to be generating the most amount of excitement, as it has been one of the most requested games to get a PS4 Pro patch. While this still isn't considered a Pro Patch per se, the Boost Mode does have a positive effect on Bloodborne's framerate, particularly when mobs of enemies are on screen at the same time. One of the most notorious performance killers for the game has been the Witches from Chalice, but Boost Mode cleans it up considerably.
Here are a couple of comparison GIFs courtesy of NeoGAF.
It still isn't 60 FPS, but as you can see, the slowdown has been almost entirely eradicated. This isn't to say that Bloodborne won't get a Pro Patch at some point (it certainly feels like a candidate), but Boost Mode appears to be a perfectly suitable substitute for the time being.