My daughter was in the front seat--airbag turned off. She was in the back seat for about 5 days. It's recommended that they be in the back and I'm sure some states require it, but it's legal here. I felt like I was a safer driver being able to coo or pass a bottle, or adjust a visor, then trying to figure out what was going on in the back seat with a rear facing car seat.
Also, excellent reasons to have the child in the front seat. Rear facing is as safe as it can get, imo.