I did some analysis of the browsers accessing Wikipedia, to get
an idea of what the software should be optimized for.
By far the most accesses to Wikipedia use MSIE 5.X and
MSIE 6.X, with over 1.4 million accesses from those browsers.
Nothing else even comes close (and they are about equal to
each other).
Next are the Netscape 4.X family and compatibles, with
180,000 accesses. Obsolete, but apparently still popular :-(
Gecko-based browsers (essentially Mozilla, Galeon, and a few
stragglers) account for 140,000. (barely beating out Googlebot).
Other Netscapes and compatibles add up to about another 140,000.
Konqueror and Opera show up at 18,000 and 8,000. Lynx is about
2,000, below even some off-line tools like Wget.
I have no idea who or what "Wikipedia Spy" is, but he's accessed
the server 406 times.
The practical upshot of this is that any code changes we make
that affect the HTML output should continue to be tested on MSIE
5 and 6 (both if possible), Gecko, and (alas) Netscape 4.