THOMAS STROMBERG  Wow, thanks for the heads up on the crashing. Right now there is not a logfile being written to, but you can see all of the logs by opening up Applications -> Utilities -> Console. If it is still causing you problems, can you open a bug at http://code.google.com/p/namebench/issues/list with the log messages? I will take care of it ASAP. Thanks!  
(Version 0.9.3)

THOMAS STROMBERG  The only technical reason there is no PPC build is the lack hardware. Xcode does not give me the option to cross-compile this, likely due to the PyObjC dependency. If you have Xcode, feel free to download the namebench source and open up the project file to build a PPC version (and send me a copy to host!)  
(Version 0.9.2)

THOMAS STROMBERG  Works fantastically under Snow Leopard. So many applications are already using the brushed metal look that it is actually hard to see any difference most of the time.  
(Version 3.0B1)

THOMAS STROMBERG  As mentioned elsewhere, this utility does not change any of your settings, but merely provides feedback on services such as OpenDNS which may be faster for you.

As far as MU checking this project out, it's my 20% project, and fully open-source. See the source code for yourself! Each of the candidate nameservers, other than your ISP's, has been reviewed. namebench does test to make sure that commonly used sites such as Google and Paypal are not hijacked, and reports if it sees any other suspicious activity with candidate nameservers including your ISP's.

One note: The Mac OS X frontend on the current version (0.9.0) does not have congestion detection enabled, so the result quality is somewhat degraded if you have a very slow connection or are downloading large files in the background. This will be rectified in the next release.  
(Version 0.9)