I remember, after my very first-ever install of WordPress, seeing "Hello Dolly" being listed in the plugin list, and being very, very confused. (It didn't help that the plugin had some incredibly grandiose but terribly uninformative description, as I recall.)

I had no idea what the plugin was, or what it was supposed to do; whether I should activate/deactivate it; whether I could safely delete it.

It is for those reasons - that it serves no useful purpose for a WordPress *user*, is intended specifically for a WordPress (plugin) developer, and is/can be confusing for a new WordPress user - that I support removing it from the default install.

Of course, Jeff, why not advocate a custom *developer* install of WordPress, which could rightfully and meaningfully include Hello Dolly?