As far as I'm concerned, a cell phone in a moving vehicle is one of the most evil things ever put on Earth to tempt mankind with.
Doesn't matter to me if you're texting or just talking on the damned thing, your attention isn't on your driving, where you're going or what's going on around you. There is NOTHING that'll double the powder and shorten the fuse on my temper while I'm driving as quick as looking through a rear vehicle window and seeing another idiot either with their ear pinned to their shoulder, or their thumb moving on the cell phone buttons like they've got the palsy or something.
When I sit down in the driver's seat, usually the first thing I do - before putting the keys in the ignition, or strapping on the seat belt - is thumb the ringer volume on the cell phone down to SILENT (if it's on vibrate, I can still hear/feel it) and toss it in the damned glove box. My wife has learned not to call me when she knows that I'm driving, and I'm slowly but surely training the rest of my extended family by simply not answering the damned thing when I'm driving. The only reason the cell phone is in the car with me is so that it can be used at either end of my traveling, or so that I can summon rescue services when some twit is more focused on his iPhone than the jerk that just cut him off.