I haven't done a Super Search on it, but I suspect that there are just short of a few billion threads about the XP system. One day, when I get bored, I may look 'em up!

Do yourself a favor: don't.

Most of them consist of newish users arguing, often quite strenuously, that their (sometimes rather harebrained) ideas for how to improve the XP system should be implemented, and the people who have been around for a while explaining why it either isn't practical or wouldn't be that much of an improvement. (Occasionally a good idea is suggested, in which case sometimes it is implemented (usually by tye), and sometimes not.)

Most of the rest of the XP threads consist of people (presumably people whose nodes got downvoted) complaining that everyone should not downvote them, but reply or /msg them instead. If I never see that particular complaint again, I shall consider the PM reputation system to be a success.