I have absolutely no problem with this. NCL has also been at $12 for over a year now.
The $10/pp/pd gratuity has been around for over ten years. Complaining about the increase really isn't too valid. Have you not had a raise in ten years? Is there just about anything that costs the same as it did ten years ago.
As Kuki pointed out, many people think that it should be included in the cruise fare. I also believe it should be. However, I do know that this will increase the price of the cruise and that, rock bottom, seven day, $349 cruise fare will now be a $433 fare.