As most of you, I experienced the world of public wikis for the first time as well, and...I felt like a child moving the first steps out in the big world!
The wiki we contributed to last semester was "OUR" wiki, we could write about things we liked, using the words we preferred and pretty much following our own rules! We were in a sort of familiar environment, whereas now we have been pushed out of this "nest"! And the rules are very different...
No more slang, no more "I": the key words here are facts, evidence, formality and impersonality!
But after the first impact I have to admit that it didn't go so badly! I had the impression of really being contributing to something important and useful for other people! As soon as I have time I'll try to see if I can edit some pages on Wikipedia as well; it's awesome to think that one day someone could look for a word on this online encyclopedia (as I have done many times) and use for their research something I have written!