I bought this game earlier today when it came out, and so far I am pleased, which is, for me, saying a lot of a high-score game.
As I said earlier in this thread, I am by no means a high-score gamer as I prefer a bit of a deeper gameplay experiences, and I'd never even bought one before Monster Dash. All the other games of this genre I had played (they are not many, I have to say), I got for free during promotions, and they'd never live very long on my iPod.
Maybe, obviously because I didn't play a lot of these games before, I can't be jaded by the genre and I can't say that I'm tired of it. But I am having a fun time with this one so far. I can't say, however, how long it'll keep me interested or how it compares to the big names of the high-score genre.
I know that the dev, Halfbrick, have an impressive record of keeping their previous game updated with lots of fresh content. Maybe it'll help keep me interested in this one.
A couple things I noticed while going through a first few runs:
The game needs new physical obstacles outside of spikes. The change may be only graphical, but spikes after spikes after spikes is boring. I'm thinking, pools of monstrous acid, bombs, that kind of happy things.
Another physical obstacle that could be fun to have is something that makes you bounce back if you fall on top of it. Trampoline, old mattresses, pile of corpses

... Maybe this one would be too frustrating to handle, however, as you would sometimes bounce back right into a pit and couldn't do anything about it. Just an idea.
New weapons and environment go without saying, but I'm pretty sure the dev are already hard at work on these ones.
Well, these were my my early impressions and feedback, from someone who usually doesn't like this type of game. You at least got me to enjoy your game guys, so I'd say great job here.
