I don't think winners are chosen purely on vote average or popularity. There may be a final selection panel of some sort that decided the winners, and given that they are human, their choices will be quite subjective. So don't worry too much about it. Not winning does not mean your article's bad - just that the judge or judges did not like it for some reason. :-) As you can see from your post rating, people were mad at you for merely asking this here : 1.73/5 (5 votes) I personally think it's a valid question though in future you might want to email Chris directly! It's kinda awkward to ask in public why you did not win.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
My latest book : C++/CLI in Action / Amazon.com link