Dexter Sneak Peek.

The Dexter premiere is available for a short time online.  (Password: sneakpeek)

I just finished watching it.  It's uneven, but first episodes usually are -- they have to introduce all of the characters, their motivations and all that junk.

The weakest bits were the flashback sequences.  But Michael C. Hall's voice-over/narration is perfect -- his delivery is deadpan and really funny. (If you go in for dark humor -- I wouldn't recommend it to those who don't.) 

The scenes between Dex and Sergeant Doakes (who figures in largely in the second book) were AWESOME. 

The storyline is following the plot of the first book very, very closely.  I'm curious to see if they'll wrap it up in a few episodes or expand it to last the whole season.

Due to Dex's nature, the show definitely won't be for everyone, but if you like the books, you'll be happy with it.