Storyline is poor, but I enjoyed the movie as it has some funny scenes and dialogues and the acting was good. Most of the Indian reviewers will surprise you as they think: movies like Karan Arjun is flamboyant, movies like Main hoon na are super hits. To me, these 2 movies are boring (boring means: typical formula of bollywood) with boring acting of Shahrukh Khan. But these are blockbusters, so don't really believe these comments. Go and watch it. You will enjoy and forget, it's not a memorable movie but it will not bore you unlike other silly action, romantic, exaggerated sensitive movies ( like Karan Johar :) ) and some other Directors.
To me, this movie is average, but it's much better than other super hit movies , I will give it 5. Hritik Roshan special appearance is good, he did the dance sequence very well. Rest is good, it should not be that bad for an Indian audience as they are habituated to watch much worse movies, so I hope this movie is okay. Story is written over here, read and decide. :)