Very pretty interface and good features.
We have our own debugger/profiler with a similar feature set (not as pretty though) that is integrated into our frame work. One of the MOST important features that we integrated into our profiler was the ability to log/save the profiler data when a page generates slowly. Basically, store your profile output and all client info to a database when a page generated slower than some time setting. You'll be surprised at all the slow pages. A page may generate fast when you are testing but under real load you'll uncover a slew of information that will help you fix/improve your application.
Under a heavily loaded site under real usage you'll see which queries are locking and are interdependent on others.
You'll also run into the issue of slow clients where you'll see slow page generation on larger pages which is attributed to apache flow controlling php.
Adding this facility into a tool like this should be easy, and it will yield a lot of useful additional data.
I wrote a thing like this (less pretty, but same information + cache stats) in PHP ages ago when I still did web frontend work, based on some ColdFusion thing someone demoed to me.
Total hack, but our site's response times went down a few hundred percent after I enabled it for developers.
Real profilers are better for directed optimization, but things like this are super useful for getting ambient awareness of how fast/slow things are and encouraging people to keep things speedy.
Nice work.