Most websites' primary traffic source is search engines, the lion's share of which is Google. Websites that are otherwise are rare, so optimizing your pages to

Most websites' primary traffic source is search engines, the lion's share of which is Google. Websites that are otherwise are rare, so optimizing your pages to match what people are searching for is pretty important. You can innovate with in-site search, and StackOverflow does, you can browse by tags, you can do string searching, you could even do interesting things with analytics regarding who browses what questions when, but if you can give people a page that corresponds to what people are looking for on Google, then that'll deliver a lot of value.