It's a pretty big commitment, if you do it right. You want to make it interesting. You want to write enough to keep people interested, but not so much as to overwhelm your friends. You want it to entertain. You hope that sometimes it'll even make a difference.
My friend Hillary Kate has started a blog this weekend, and I checked it out last night. She is a student at the University of Alabama, and is the friend and roommate of some pretty cool gals (my nieces Haley and Macy). She is a smart, funny, interesting young lady, so I know her blog will be the same. It has definitely started out that way.
It's called The Ginger Chronicles, and in addition to this link, it's listed to the left of the page. Check it out - I think you'll enjoy it.