_qwerty_
1. I believe that there is a link between ego/confidence and being creative/innovative. To consider or suggest doing something different --whatever the domain-- takes self-belief - the confidence that your ideas are better than the prevailing status quo that the rest of the world is satisfied with.
2. Mostly, in addition to #1, I see being creative/innovative as just a mental habit. Some people examine the world around them critically, and want to improve some aspect or other, while others don't. Practise this sufficiently often, and you'll improve, as with most pursuits.
(1 & 2 would become a virtuous cycle - you believe that you can improve things; you more regularly look for opportunities to do so; you [get better at] find[ing] them; you [or others] provide positive reinforcement.)
3. Personal belief: there may also be correlations with certain personality types. For example, people with certain traits may be more prone to noting imperfections in their experience of the world, leading directly to the thought processes which result in ideas for possible improvements.
4. I think you're conflating being creative with actively pursuing generated ideas or opportunities. The difference may just be circumstantial: that someone lacks the financial wherewithal to pursue an idea, or for personal reasons (e.g. conflicting responsibilities) can't dedicate the time or energy to pursuing that idea. Action ≠ creativity. In fact, the opposite may often be true: it's well noted that creative people need to be teamed with people that can/do execute their ideas fully (e.g. 'implementers' and 'completer-finishers' in Belbin's team-roles).
For example, with sufficient data to analyse, it shouldn't be tremendously difficult to find relationships between users who tend to agree or disagree, and provide each user with a customised view, taking these preferences into account.
(Of course, slashdot took a slant at making it cleverer - by allowing upvoting for different reasons - e.g. funny vs. insightful.)