Blackberry Addiction

Have you got annoyed by someone you know keep checking their blackberry while spending time with you and talking to you?

Have picking a vacation destination without internet connection and mobile connection part of the requirement?

Blackberry gave me a lot of flexibility and convenience so I don't have to be glued to my desk and my computer all the time.  However, when it gets into your personal life too far and you don't know how to draw the line between your personal time and work, you got a huge issue.  Does blackberry enhance communication or impair communication?  Has it interfere with your personal life?