I'm a college senior going for a BS in computer science and a BA in English. My contributions are usually limited to fixing broken windows, because I generally don't have time to create Wikipedia-calibre articles. My philosophy is to be bold when editing, and then never return to the page so that I don't feel any distress if someone else decides I was too bold and changes it. This also helps to avoid revert wars and other WikiStress. I try to avoid mistakes whenever I can, but one of the great things about Wikipedia is knowing that if I slip up, anyone who notices my mistake can fix it. And, it goes without saying, if you think I've edited a Wikipedia article in a way that is less than perfect, by all means, change it at will.
I get a guilty voyeuristic pleasure out of reading nasty debates in talk pages, but I try never to get involved in debates myself.
As my 10th grade English teacher Mr. Fick used to say, I believe in Anapaest Destiny — that America was put on this Earth to promote the use of a metrical foot of two unstressed beats and one stressed beat. ;)