Osaka is boring :) It is just my personal opinion and I realize that it is not objective, but rather a result of a number of factors.
Let me explain, I only visited it once on the way from France to Toyama. I only got to spend one day there because I arrived on a plane and took a train in the evening. I only visited the castle of Osaka and the downtown, I was not really in the mood for sightseeing I was tired after 12 hours on the plane and wanted to get to my destination. I don't remember if it was Fall or Spring, but it was very grey and a little bit raining. So the weather didn't add any excitement to the trip.
Yeah, this is not an attitude to have while visiting a new city, but come on, one of the city's most prominent tourist attractions is a billboard for confectionery company :)