It might be a nice idea, but for the usual reasons, it's not really possible. First off, some posters will lie to make themselves feel better. Others won't want to give away the specs to their valuable $15 dollar 486 box, and so on. Most people that sign up probably just want to ask a question, not really wanting to fill out a mile long questionare to see if anyone here can actually help.
That said, it would be nice if the occasional person listed at least their distro...
