I saw this in New York in September largely on the basis of Zachary Levi being the lead. I'm not a musical theatre/showtunes fan so I went in with some trepidation, but ended up being impressed. The songs may not rival Sondheim but they are catchy, cute, funny and convey genuine heart. All the cast members have a chance to shine, though poor Kate Loprest is a bit underserved after one of her songs was cut in previews (through no fault of hers, she's extremely talented).
The show is due to run until January 2014 so if you can get along to see it, do so. Even if musicals aren't your bag, it's funny, sweet and you're done in 90 minutes.