Hmmm I'm not sure, but I think Kyon's words is almost as heavy as Haruhi's. We should believe that episode 0 is episode 1 according to him lol.
So far AniDB is the only site with more details about the number of episodes:
http://anidb.info/perl-bin/animedb.p...anime&aid=3651
But they aren't completely sure themselves, like all other anime websites. In the 1st 3 weeks, anime websites have been saying that Haruhi will have 13/14 episodes, but now every one of them has removed that and in place we have 'N/A', '0' or '-'.