It is a good number as an average for a game that doesn't include multiplayer. I have 1,021 hours in Skyrim myself, but there must be thousands at the other end of the scale who have played a few hours, just done the main quest and put the game away and played something else.
To Bethesda that could mean they wasted a lot of time and money creating all the dungeons, characters, side quests and guilds that those people never saw. There is a chance that there is content in TES:V that less that only 1% of players have found. Bethesda have to ask themselves when they are budgeting for their games whether it is worth making such content.
This is why I think Bethesda didn't go heavy on the choice and consequence side of RP'ing in Skyrim, and having multiple endings to all the quests. It would just mean they are creating content that will never be seen by the people (and there's lots of them) that just play the game once.