At the time I thoroughly enjoyed the movie...from start to finish. Personally I thought Michael Keaton was just fine as Batman. It's called acting folks. People get in their minds how a person is 'supposed' to be when it's all make believe.
The `50's vibe along with a 'noir' feel made the whole thing work. The chase scene tickled me with the bad guys hanging out of the car shooting in all directions...it took me straight back to being a kid on Saturday mornings IN THE FIFTIES ...it was a hoot. IMO it was one of the better movies in `89 period....pure tee fun.