Sony Computer Entertainment just announced that Bloodborne's patch 1.03 has now been made available for download on the PSN. Below you can see the patch notes.

Main points of UPDATE　1.03

• Reduced loading times (approx. 5-15 seconds; may vary by circumstance).
• Fixed bug that left certain lifts and elevators inoperable.
• Fixed bug that resulted in bosses becoming immobilized.
• Fixed bug that left players unable to advance NPC events during multi-play.
• When the PS4 is put into Rest Mode during online play, the game will now return to the main title screen upon resuming play. This will resolve matchmaking issues related to Suspend/Resume.
• Other various bug fixes.

Incidentally, the Update History on PS4 also mentions "Improves games performance," even if no specific details are provided.