Okay, I'll say it. I like the idea. I don't mean to be contrarian; but, I think a little bit of "Frozen" is exactly what the World Showcase needs. Epcot as a whole is in desperate need of another Tier 1 attraction. Yes, Epcot and the World Showcase are more adult oriented to begin with; but, it is still Disney.
I understand Disney's desire to capitalize on Frozen's undeniable popularity, but I am firmly against making the Norway Pavilion in World Showcase its epicenter. There is absolutely zero correlation between the movie Frozen and the intended purpose of the World Showcase pavilion, sans the fact that the movie's scenery is based on Norway's countryside. That to me is not a sufficient enough reason for plunking it there. It is largely understood that Disney's interpretation of Cinderella (one of their most popular animated movies of all time) is based in France. Snow White... Germany. Mulan... China. Why stop at Norway... Let's just blow up World Showcase as we know it and turn it into New Fantasyland-2. Lord knows the MK version is rather unimpressive... maybe they'll get it right in EPCOT.

(that's my effort at a little sarcasm)
I have to agree with another poster in that the ride just seemed confusing and horribly dated.
I'm not sure what's so confusing about the ride? It takes you through time, from the days of the Vikings up to present-day Norway, much like Spaceship Earth takes you from our start as woolly-mammoth hunting Neanderthals to modern-day astronauts. Sure, the trolls aren't factual, but are definitely a part of Norwegian folklore. I won't argue the fact that the ride feels a little dated (OK, maybe that's an understatement).
I always hate to see any attraction removed. Epcot as a whole is in desperate need of another Tier 1 attraction.
World Showcase is not, nor has ever been the problem in EPCOT. Future World, on the other hand, is abysmal. The Imagination pavilion has about as much demand as an ejection seat on a helicopter. Universe of Energy / Wonders of Life pavilions are totally stagnant. The only two draws within all of Future World are TT and Soarin', and that, my friend, is the problem within EPCOT. Lack of investment, lack of Imagineering and lack of innovation in what is supposed to be the portion of the park focusing on technological innovation (how ironic) has led to this. World Showcase, on the other hand, was meant to focus on international culture. Explain to me again how converting Maelstrom into a Frozen ride fits this bill?
Yes, Epcot and the World Showcase are more adult oriented to begin with; but, it is still Disney. Smaller kids, particularly girls can get bored with Epcot relatively quickly.
Much like us adults can get quite bored in say, New Fantasyland? The majority of MK is geared towards kids. World Showcase is the one area in all of Disney World's theme parks that really is geared towards adults. There has to be some balance, yes?
I have no doubt the Imagineers can tastefully blend a Frozen ride into the rest of the Norway pavilion and breath a little fresh air into a stale area.
We can only hope that this is true, and I suppose I should reserve judgment until we see the finished product, but I just can't help overcome the notion that a Frozen ride just doesn't fit in World Showcase. As I previously mentioned, New Fantasyland I feel to be a snoozer, with the exception of SDMT. That would be the perfect place to put a Frozen attraction, and they could have had a blank slate to start with, rather than trying to fit a round peg into a square hole by working with whatever the Maelstrom platform can offer them.