Here are this week’s links:

• 50 great examples of infographics – Curiously enough, these excellent, cool, examples are surrounded by annoying animated internet ads.
• Secrets of Amazon.com sales ranking – Some details I hadn’t heard before about how the rankings are computed (weighted over time).
• How Twitter’s staff uses twitter – In the irony department, here’s all kinds of data about how tame the use of twitter is among the people who work at the company.
• How to think constructively about healthcare – Great charts and data about how U.S. health care compares to other nations. (Hat tip: Cesar)