Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I just noticed while i have my phone plugged into my computer, charging (and listening to music), the phone doesnt autolock. Is this normal? I never noticed that before.

Yep, this is normal. It seems to be this way to allow you to show off album art. (It's one of my pet peeves.)
 
I always assumed it worked this way for iPod/iPhone speaker docks, so you can always see what is playing.
 
And also, you can now access/use your phone while you're synching it. It does the synching in the background. It will show a circulating arrow by the carrier name on top. This is a new thing on iOS 5.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.