Raced through the first four episodes, absolutely stunningly good show. If they keep up the quality for the final half (a big ask) then they've made one of the greatest tv season's of all time.
At first I was disappointed to find out its only one season, but the more I think about it, the more I like the idea of a new story and cast every year, instead of dragging out one story which is really what tv's biggest problem is these days, though shows like Breaking Bad show its not impossible to end at the right time. Keeping this as a story told over 8 episodes should ensure it doesn't drag and comes to a natural end, I think a detective show is probably the hardest type of show to keep going too without it seeing forced.
Interesting to see what kind of cast they get for next year (I presume it'll be renewed) I can imagine a lot of big names seeing the hype its getting would be very interested, whilst the chance to emerge yourself in a character for 8 episodes must be enticing. Not like 8 episodes is a big commitment either.