Another one here for Levis. I change into scrubs at work, but I ride to work or just around town in jeans until it gets over 60F, then I switch to bike shorts. Rain or shine. I haven't noticed any additional wear in the seat, nor have they gotten any grease smears that Dawn wouldn't take out.

For background - the town I live in is about 5 sq miles, I ride a Schwinn 87 Tempo, and my commute is 3 miles one way. I work a 10 hour shift, so even if my jeans get soaked on the way there (like tonight), they are dry by the time half my shift is over. (I just checked them, and they're only slightly damp still - maybe I'll stick them in the blanket warmer before I go home) I have a hi-viz rain jacket and helmet cover too.