Yesterday I called someone on their mobile phone. THEY ANSWERED! When I started the conversation, I was told, "I can't talk now, I'm in a meeting." Now, I know two things about this person:
1. The cell phone & everyone else runs this persons life/schedule. There's no proactive control of the SmartWeek as Floyd would say, and
2. They only think of themselves most of the time.
I've always found it a little strange that people feel bad (or a little embarassed) when they've interrupted someone in a meeting or other activity calling a cell phone. Here's my attitude: You answered your phone you idiot so no one interrupted anything but you!
If there's a chance you won't want to have a conversation, don't answer. What message are you sending to your caller? That you're not as important as the person I'm with now? Most of the time that non-verbal message will be sent to someone with much thinner skin than myself.