Forrester stresses the importance of factoring in geography when making cache decisions but points out that IT shouldn't confuse a dense population of customers with the company’s best (read: most profitable) customers. "Caching nearest to your users goes without saying, but most companies must allocate their caching dollars carefully, and your biggest investment should be close to your most profitable customers. Your most profitable customers may not be located in your highest concentrations of customers. Work with your marketing department to analyze customer profitability and location, and then review this data at least annually."
Although retail sites are obviously very fond of cache, a new report from Forrester Research states that many developers are focusing only on one type of cache and leaving a lot of potential performance boosts in the ether. The report talks about server cache versus browser and edge cache. "Forrester has found that many companies do not take advantage of all three levels of caches in their architecture. Application development professionals often focus on optimizing the server-side cache while ignoring the browser cache or optimize their Web-page design to take advantage of browser caching only to be stung by geographic latency because they don’t know that they should use a content delivery network."