I checked it out and you've got slick graphics, a decent description and a video - that's a good start. From here I'd try and get some interest on the toucharcade forums and see if you can leverage that into a review.
From a potential customer point of view, the idea is interesting, but I don't quite see that it would lead to an interesting game - and the video didn't really change my mind. It seems like at its base is a simple and quite slow game and each level some minor thing is different. It didn't look hard, or exciting. If it gets action packed or tricky in later levels maybe you could put one of those levels in the video.
It does get harder, yes. Some levels are hectic, and some levels are tricky. And there are some surprises along the way. It's a bit hard to capture the difficulty in a video since what's different is, well, invisible. And also I don't want to give away the solutions to the more interesting episodes (or ruin the surprise). To quote Osmos:
"Is there a demo of Osmos I can try first?
Yes, but don’t let it fool you. The game starts gently, but there are some truly difficult levels later on in the full game."
Well disclaimers don't actually mean anything to anyone. It is worth ruining some of your good levels to get customers. If someone plays the game, loves it, and wishes they hadn't had a couple of levels spoiled for them - thats a win for you (and for them mostly, they probably wouldn't have played it otherwise).
Also I just played "This Is The Only Level" as per waxpancake's comment. It's a fun flash game, but it still seemed fairly disposable. The thing your game has all over it is the graphics - but you haven't really given it any character - your dragon and princess don't say anything. A bit of humour and characterization goes a very long way in fun little iphone games.
Character is important! In Plants vs. Zombies there's that crazy guy named Dave who sells upgrades and says ridiculous things. Each plant and zombie has a distinct personality you can read about that's fun and goofy. There's visual jokes as well. And the end-game music video is an awesomely silly reward for all your time spent playing. All of this adds up to an experience people feel connected to.