The cell phone is extremely convenient for me. If I need to drive 30 minutes to get to work some days, I can get a phone call or two in, also, instead of doing it later when I'm at home and have other things to do. Also, in case of emergencies or last-minute change-of-plans, it is very nice to have.
On the downside, I can't stand it when people call me on my cell phone without trying my home phone first and/or when they call me on my cell phone and it's not an urgent matter. I don't do it to them!