Even though the majority is for No, ~1.6m voted for radical change. This was not a "nationalist" movement. It was a movement of ideas (the breadth of the campaign has been astounding). A majority of the ~2m that voted No did not vote for the status quo: they just thought the risks too great.
On the contrary, the media insisted for weeks the referendum was "too close to call", citing endless polls that generally favored the 'no' vote, but were close to 50-50. Obviously people vote more conservatively when it matters.
Meanwhile, the bookmakers, who actually had skin in the game, knew a 'yes' vote was unlikely, and reflected that in their odds.
(I don't know either way, not being paying much attention to the press, though BBC Scotland has seemed quite balanced)
They were biased because they consistently took a negative stance towards the potential ramifications (not chance of outcome) of independence.
The possibility of Scotland voting for independence had that in spades; nobody really knew what it would entail.
Thus the media persisted in presenting it as a realistic, likely prospect, even when it was quite apparent (as per bookmakers odds) that a 'yes' vote was very unlikely.
If the media, who overwhelmingly supported No were reporting it as "too close to call" then either a) they felt that was the most effective way to bring about the result they desired, or b) they are idiots who don't understand the basics of the things they report on. Probably a little of both.
http://www.dailymail.co.uk/news/article-2755858/BBC-s-Nick-R...
That is, in fact, strictly what the article says, but not how people are encouraged to interpret it.
This single event spurred the whole BBC protest, and brought widespread attention to actually quite a lot of small, arguably subtle but definitely existent, biases in the reporting.