Admittedly this type of film isn't really my thing but I went along today to see it anyway.
15 minutes in I was so bored, the cinema was hot and I had trouble staying awake. The best bits were the scenes with Sacha Baron Cohen & Helena Bonham-Carter.
The others were all good in their roles of course, Hugh Jackman, Anne Hathaway, Amanda Seyfried, Russell Crowe - I don't mind musicals but when conversations are sung it all gets a bit grating. The audience loved it and applauded and cheered at the end. It was more of an endurance test for me though.