I am here to do my part in diminishing the value of all the one- and three- star reviews posted here, the authors of which are clearly the same person or all from the same class of children too young to read the play. Amazon visitors reading these should know two things: the reviewer is a twit, and this play is wonderful.
I, for one, am a sucker for romances; if you are, Beatrice and Benedick will make the play worthwhile. Predictability be damned, they were an adorable couple. The main couple, Hero and Claudio, are boring; the other one will make you swoon. Beatrice and Benedick are funny, clever, and stubbornly reluctant to admit they love each other. To wit, they're perfect for one another.
I have read two contradictory criticisms regarding the language in the play on Amazon: that the language is too simple for Shakespeare's standards, and that the language is too difficult. The latter was from the kid's reviews; for everyone else, the language is not so difficult to decipher that you need to avoid it. The Folger edition, at least, has one page of notes for every page of text, noting both puzzling references to Elizabethan beliefs, such as that sights draw blood from the heart, and language problems caused by the hundreds of years between Shakespeare's time and ours. The editors do all the work for you. You have no excuse. (Oh, and that the language is too simple: Bah. It's Shakespeare. That's impossible. I loved all the double entendres; this play was very witty.)
One criticism I somewhat agree with is that the plot is boring. Hero and Claudio, being the main couple, get much time, and I didn't care much about Don John's vengeance, but at least half of my favorite couple was usually present, and by no means do Hero and Claudio's plot monopolize the story. Much Ado About Nothing is often genuinely entertaining, which is what kept me interested. The plot's not the point here, it's the dialogue.
In sum, the language is poetic, but not so much so that it reads like Klingon, the romance will make you sigh, and the plot is at least good enough to keep Beatrice or Benedick in most of the time. Don't let the previous reviewers deter you: Read it.