Is it sad that my favorite thing about Knight and Day was that the female lead was competent and skilled without being an exception (i.e. super-spy, femme-fatale grifter, etc.) or an anomaly? Perhaps. But my other favorite things were how well-written the story was, and how it didn't need to hit you over the head with obvious plot resolution moments. It assumed an alert and intelligent audience without being overly coy or obtuse. That is a rare thing these days, and was immensely refreshing as well.
It's gone now from my local cinema, making way for Predators (saw yesterday, liked, more later) and Despicable Me (which I really want to see but will choose a showing less packed with children than opening weekend matinees are likely to be). If it is finished with its theater run, there's always rental. But I'd love to see it make enough box office to make it easier for Patrick O'Neill to have a chance at getting more screenplays considered.
Either way, it's worth seeing, IMuHO.