My experience... I was having problems with my D2 (went through 3 in 2 weeks), called VZW customer service and the guy insisted that he could not help me as long as I was using the phone that I was calling about (that's a whole nother story/issue for another time). After hanging up with him, I received an automated call asking me to take their survey. I gave low grades, and at the end when they ask for recorded comments, I emphasized my displeasure with both the low level of customer service I received, as well as my overall dissapointment with the quality of the D2s I had been receiving.
2 nights later, I get a call from a guy at VZW QA following up on my survey, asking me how he can make things right. Long story short, my new DX should arrive tomorrow, free of charge, no contract extention.