Released as a two hour movie event (even in theaters in select cities) Razor is a bridge from season three to the upcoming and likely final season starting in April (assuming the writers strike is resolved).
I won't dig into plot, summary and spoilers because I think you either get and watch BSG or you don't and if you do then you probably were aware and excited enough to have watched/recorded/downloaded and savored Saturday night's extended episode.
I did. 5/5. (Review Link)