The second episode of Life on Mars was stellar but it lost 17% of its audience from last week. However, its time-slot rival, The Eleventh Hour, managed to increase its audience.
I think this is more to do with the lead-in than the quality of the shows. The Eleventh Hour gets CSI (18.8 mill) and Life on Mars gets Grey's Anatomy (14.4 mill). The ABC remake also needed an inheritance from something in the same genre ballpark, like Lost, for full momentum. The ratings still ain't too shabby so fingers crossed that they don't dip further.
Here's the first episode. Would you watch episode 2?