Depending on your audience, the following issues could arise and should be considered when analyzing site performance and visitor behaviors: Cookies, Pathing, Web browsing behaviors, Time on site, and Paid search.
Web browsing behaviors are constantly changing. As a result, analysis of those behaviors must evolve to match those changes. A recent change that has become more prevalent over the past few months is tabbed browsing. The Firefox browser made tabbed browsing much more common, and now Microsoft has added it to Internet Explorer.
Tabbed browsing allows people to open more than one window within a browser and easily bounce back and forth. If you haven’t already discovered tabbed browsing, check out this example.