Another vote for leaving the exif in tact. Exposure information is interesting- how slow of a shutter did he/she use to get what kind of motion blur or panning or whatever. F stop is good to know for reference, as in how much or little DOF did they achieve? Focal length is a good one also...and ISO. A lot of times when I see an amazing image, I check these things to see if I've got similar equipment; hoping, that I don't, so I have an excuse as to why I can't capture equally impressive images!

Exif is especailly useful in helping someone diagnose what went wrong with a photo... So, yeah, keep it in!

BM