Yea, the intermediate tutorial is pretty long. I actually really enjoyed that when I first found the game in July '09, it let me play a fairly interesting (for a new player) scenario in trial mode.
The actual game is considerably more interesting, but it certainly isn't any shorter. To some extent the intermediate tutorial's length is just honesty-in-advertising: if you don't like long games this might not be something you want to buy (though Defender mode in the LotS expansion does allow for games shorter than an hour, it's just not the same type of scenario).
And the tutorial's already pretty focused, in that it's a step-by-step without too much else going on. The real game has much, much more going on