When I read the summary, I wasn't expecting much. However, it ended up to have a pretty cool story. I love the alternation between real world and the cartoon world. I think it was a great idea.
The characters are interesting and the revival of cartoon characters taking over the story of the manga themselves is somehow supercool.
The ending keeps you on your tip toes. It is a bit predictable but it still has elements that keep you interested.
All in all, I would recommend this as one of my favorite dramas.