I just did this breakfast on Feb 12th with my dd(6) for her birthday. It was her dream to eat with the princesses. I normally avoid character dining because the food is mediocre and despise buffets where you feel like you have to eat $40 worth of food to get your money's worth. I just don't eat that much.
I was pleasantly surprised at the quality of the food at the breakfast. The fruit was perfectly ripe and the breads/pastries/cheeses were very tasty. The eggs were kind of fake tasting, but the bacon (which I requested extra-well done) was really, really good. We had excellent service, as well. They offered substitutes of cereal if my dd didn't like the hot breakfast. They also offered veggie sausage.
Overall, yes, you are definitely paying for character interaction. If you get the earliest seating, make sure you request a table near the beginning of the princesses' rotation so you aren't sitting there waiting for 30 minutes even after you have finished your breakfast before the first princess gets to your table. Our princesses were Ariel (you always see her at the beginning before seating), Cinderella, Snow White, Aurora and Belle.
Oh, and I think you can pre-purchase character meal vouchers at a discounted price from getawaytoday.com.
EDITED: NEVERMIND, just read on another thread that the getaway vouchers aren't valid for Ariel's breakfast. That makes no sense, since it is the same price as lunch. Sorry.