True Blood is an excellently written series. I have watched it since it began, and recently bought this dvd set for my nephew. It is nothing like the Twilight series, and in my experience, people who really love Twilight usually do not care for this series - again, simply because the two are nothing alike. Some of the main characters here (as well as supporting roles) are vampires, but that's not to say this is a show "about vampires." This series is really best described as being about the people and goings-on of a small, backwoods Louisiana town where some of the people just happen to be vampires.
As mentioned above, the writing is excellent. One of the best aspects about this series is that it is definitely NOT predictable! Not in the least. You never know where the writers are going to take you...from one episode to the next, or from one season to the next. The character development, story lines, acting, directing, casting and effects are all first rate. Considering that the series has its fair share of killing (although not overly so, and it's certainly not the focus of the show), the series couldn't be called "dark" or gory by any means. I also would not call this show necessarily "violent" either. (Personally, I don't care for violent shows or movies, and I find this series to be tolerable on the violence scale. It does have killing and blood and bodies and body parts, after all there are vampires in it, but even so, it's done in a way that is not offensive or vulgar.)
There is comedy, drama, action and suspense...and very well choreographed cliff-hangers to end each episode. Despite the blood, death and suspense, the series as a whole is well balanced with comedy and other character's story lines which help keep it from being overly dark. There is a quite a bit of nudity - not raunchy, but tasteful and almost artful. So if you're sensitive to nudity, just be forewarned...or simply cover your eyes during those parts, because the story lines and acting make this series well worth watching.) I easily give 5-stars to every season.
Another refreshing bonus is that the episode commentary for every season is also worth watching. The actors, directors and writers actually contribute thoughtful and interesting tidbits that add to the episodes and the series. It's best to watch the commentary after you've completed the season because sometimes they accidentally reveal things that happen later in that season.
This series is well worth purchasing.