I was having some issues with the ordinarily awesome KCacheGrind (it kept crashing, so I couldn't do anything with it), so I decided to look for another profiling tool. I finally found and installed Webgrind (http://code.google.com/p/webgrind/) and I must say that it is excellent. It appears that, after installing, you must ensure that Xdebug spits out its profiling data with a certain naming convention, or Webgrind will fail to pick it up. This is actually kind of odd, since there is a configuration option in Webgrind which is supposed to tell it what the naming convention is going to be. I could really see Apache/MySQL/PHP/Bespin/Webgrind as being a really cool environment to set up for distributed coding. But, that is a discussion for another day.