As per our rules, there are only 2 cases:

• Either it was broadcasted officially as the 1st episode of the 1st season and it should be listed as such.
• Or it should be listed as a special episode.

It couldn't be listed as you say, because:

• Episodes numbered 0 should be listed in the specials season
• A regular season should have at least 2 episodes. Otherwise, the single episode is listed in the specials season.

That's OK, but why does the main page say the show started in 2010, not 2009? That's the problem I have.

The date is based on the date of the 1st episode of season 1.