We've improved our already fantastic interactive waterfall chart with a new collapsed mode that highlights all the key browser events. This lets you quickly scan all the events that happen as the page loads and if you scrub your mouse across the waterfall you can easily correlate each event to what the user could see at that moment.
Along with all the browser metrics you also get to see our new hero rendering times in context. Click on any event to see a large version of that moment in the filmstrip.