Product Managers pay (or should pay) a lot of attention to finding out more about why people are NOT buying their product more than why people are buying their product. This can be framed based on the current population of users.
But we are at a tipping point in history where a large number of baby boomers are approaching retirement and their places are being taken by a wave of new entrants. Many of these new entrants are currently in colleges. So if you are planning to develop a long term roadmap, make sure you are taking into account the behavioral aspects of the new generation.
I thought that the survery results shown below (Source: eMarketer.com) was very interesting in understanding the adoption of the latest technology by age (Low adoption of RSS feeds in the younger age group was a surprise to me). It is important that we pay attention to this because these represent the future users of our products.
The full article is titled Baby Boomers and Social Networking and is worth a read. Pay equal attention to some of the similarities called out in the full article.