Are Cell Phones Making Us Less Productive?

I was in a meeting a few weeks ago that lasted about an hour.  Throughout the whole meeting, one person actually sat there playing on his phone the whole time.  No one said anything to him and he did participate in the conversation, but still... totally unprofessional.

I know smart phones are great.  It's awesome to have that amount of data and information at your fingertips in seconds.  I know, in my experience, that when I have a question for a manager at work all I have to do is email and I'll have a response within half an hour even if they aren't in the office.  The email response coming from their phone.

I now have a habit of checking all my different email accounts multiple times a day through my phone.    I have an app that tracks my stocks.  I check this multiple times a day, a small thrill when the price increases. 

I've also noticed everyone having their phones out on their desk all day. People walking down the halls texting without paying attention to where they are going. I've noticed people posting on Facebook throughout the day. How do I know this? I never really got into Face book until I had a smart phone. Now its just so easy to pop on and see what people are up to. I never would use my work computer to go on because that didn't feel right and my old phone made it too difficult. But what's the harm in taking a quick look with my new phone?