The reason for this are many:
1. To begin with, Sony hinted at a release within next 6 months. That means it will release between now and February 2015. Now the release schedule for PS4 exclusives currently looks like this
| September | N/A |
| October | Driveclub |
| November | LBP 3 |
| December | ?? |
| January | N/A |
| February | TO: 1886 |
Nw September release is out of question, and January is a very slow month everywhere in the world for video game sales and hence would be a bad time to release a highly anticipated game.
A holiday release would be beneficial to sales of the game itself and the sales of PS4 due to Bloodborne. Also Sony have a PS4 exclusive lined up for each month in the holiday so far, except December, and Bloodborne would be a perfect fit for that.
2. The system is not selling well in Japan. Bloodborne can easily be a system seller in the country. And there is no better time to release Bloodborne in Japan than in December, Japan's equivalent of a holiday season. If it releases in Japan in December, its likely to release everywhere in December, as Dark Souls games also have a history of releasing everywhere at around the same time.
