The fun part is that these kind of discussions pop up once in a while. The key issue is to realize that XP is not a matter of quality, but just... err.... a matter of perlmonks experience. Is correlates a bit with quality, or with coding abilities, but mostly with the amount of time spent on the monastry. Many exceptions to be found, most noteworthly Erudil, who hardly nodes, but gains depressing amount of XP with (nearly) each node he creates. We also have Petruchio among us, who hardly leaves the CB and can be found there for more than 48 hours on row. He surely contributes to the community, helping people all along (eg me as a novice). As he nodes very little, he gains little XP.
Myself, I have reached that level 10, but that doesn't tell you much. Most perl skills I have aquired have been taught to me by the monks. I am most grateful for all the help and tips you people gave me. At the same time I try to return a little bit of that knowledge to those that can use it by answering questions. Sometimes my help is appreciated and I've got myself some more XP. I am certainly not a perl guru or something. I am not even eloquent (in English, that is).
XP is also dependent on the number of people that can vote. As the community grows, the votes per post increase and so does the speed novice monks climb the stair of saintdom.
XP is more a community property than a quality assessment. However, if you take your ordinar thread, you will see that the best answer/node is on top. So actually, the XP system works quite well, thank you.
Just do not try to relate personal XP to quality, you'd better see it as Yet Another Filter to grand permissions only to those who contribute to the community.