I liked the movie, just not the outdoor scenes
A good monster movie is a movie which sets the scene and mood right. Cloverfield did a good job, in fact I kinda liked Cloverfield because it created a good mood and a good sense of anxiety (though the ending blows hard).
Now Monster movie:
The same sound effects repeated over and over, the horrible cut-paste animation and the same locales shot again and again ultimately made me laugh rather than scared. The leads and actors were good, but the animation and filming ruined it.