Bloodlines is one of the best games I have ever played, certainly the best vampire-centric game out there.
The story and atmosphere of Bloodlines are top-notch. The main story and all the side quests are interesting and contribute to the overall "dark" feel of the game. After finishing the game for the first time, I was sad that it was over. This is one of the most immersive games I have seen and it has a unique charm. Bloodlines brings you into the perpetually dark world of vampires, werewolves, zombies, and other such creatures flawlessly.
The game-play itself isn't always exceptional. Weapons are not always as effective as you'd expect (swords are much more powerful than machine guns in many cases) and combat is somewhat clumsy at times. The dialog and character-development make up for this, though. The game includes a thorough experience system and points that can be spent to upgrade attributes. There are many diverse characters to interact with and several distinct settings.
Some of the reviews you will see indicate that the game is plagued with bugs and glitches, but I haven't had many problems with these. The official patches take care of most of the problems. Additionally, unofficial patches are available that not only solve technical problems but also add high-quality content.
Bloodlines is not necessarily the best shooter or RPG on the market, but it is the best vampire game out there. The overall "cool factor" outweighs the technical problems that the game has. The little things like the great soundtrack and fitting atmospheric sounds make the experience so much more believable. As you play through the game, it becomes apparent that great attention was paid to detail.
The ability to play as a vampire alone makes this game a must for anyone with even the slightest interest in the darker side of video games. I highly recommend this game, despite its problems, and I would suggest considering the unofficial patches for added content and some beneficial changes.