The new Bloodborne patch will give you better rewards for chalice dungeons, hopefully increasing longevity by tempting you with the rarest of rocks and blood gems.
Spotted over at games.on.net and by Reddit user illusorywall, the patch notes specify that you'll get "Blood Stone Shards at Depth 1, Twin Blood Stone Shards at Depth 2, Twin Blood Stone Shards and Blood Stone Chunks at Depth 3, Blood Stone Chunks at Depth 4 and Blood Stone Chunks and Blood Rocks at Depth 5."
Those Blood Rocks were previously only available once per playthrough, from a hidden area in the Nightmare of Mensis. That's quite late into the game, so this change theoretically gives you access to a +10 weapon much earlier. Or even several +10 weapons.
Maximum blood vials and quicksilver bullets have been increased to 600, instead of 99. And once you've found Lost or Uncanny versions of weapons, they'll be purchasable, though I haven't seen anyone doing interesting theorycrafting with Lost/Uncanny blood gem combinations.
Of course, no amount of shifting blood gems around will compare to getting your evasion timings right, and Bloodborne's size means that chalice dungeons are really more about fun with friends than anything else. But it can be fun to have something to work towards, and at least gearing up will make you a little more prepared for the upcoming DLC.
Check the Reddit post for more info.