The Song Remains The Same (5x13) is the only Supernatural episode where the characters experience only one night in the episode! The episode What Is And What Should Never Be (2x20) took place during one night, but Dean experienced several days in the alternate reality - a pattern that was repeated with Dean's former time-travel episodes In The Beginning (4x03) and The End (5x04). The majority of Ghostfacers (3x13) took place during one night, but the closing scene was set days after the fact - this was probably also the case with On The Head Of A Pin (4x16). There have also been episodes that span 24 hours: Devil's Trap (1x22), All Hell Breaks Loose Part 1 (2x21), and Jus In Bello (3x12). However, TSRTS (5x13) remains the first episode to take place both in one night in the present and one night in the past! (if we ignore the very last scene with Mary being heavily pregnant.....)
Usually the boys tend to spend between 2 to 5 days in each episode, with some episodes spanning over week (No Exit and Heaven and Hell).
I know no one cares about this but me...but I think it's neat when they break up the pattern of the episodes.
Also, I absolutely love the fact that the PROMO clip for next week gives me a date! S5 has so far been the absolute hardest season to timeline. Seriously, it's all a bunch of unknowns really - I practically wept for joy when Dean confirmed it was 2010 last week - at least then I knew what year they were in!