The most important thing I want everyone to know is that it get's better. Much better.
If you love the genre, I recommend you watch through the first season as the second season is better and the third season is totally awesome.
There are many likeable actors/actresses. The acting is believable.
The special effects get noticeably better by the season.
I absolutely LOVE the story. This is my favorite genre and I'm glad I watched through the first season even though I wasn't to eager to finish it.