website or Web site

I have seen the word website written in many ways; website, web site, Web site. The last in the list is to me the most awkward way of writing it out, but the AP style book says that it is correct, is in fact the only way to write it properly, since the word web is an abbreviation for World Wide Web. Still, a lot of newspapers, like the New York Times, for example, do not write it this way. I understand this could just be the preference of the paper, but what do you think is best? What does Chicago say about web addresses? AP says the "http://" should always be included, but this looks so messy.
Also, how much fact-checking are copy editors expected to do? Names, dates, but what else? Where do you draw the line and query the author for more information?

The Author's Voice

Here's my question. I suppose it's not too technical, but I have been wondering exactly how bendable some of these rules of grammar are. I know that recently (as in the few decades) grammatical aspects such as the comma have had more open "rules" about placement, but I am more curious about dangling modifiers and the like; the words. Where do you draw the line between style or voice and what is just clearly wrong? How much can one argue that, even though a phrase is incorrect technically, it should be allowed into a publication because it's part of the author's voice. I would think it all depends strictly on the context, but is that always true? (or true at all?) Would it be okay to leave an unclear phrase in a piece if the mistake has so ingrained itself into the common language that it would make more sense to the reader left as it is?

(from Claire)