I don't really care about it being a sequal to the other movies (as either 3 or 5); and I'm a little nervous about some of the plot points I've seen. I think, after 20 years, it was time to revamp the movie image. However, as long as Singer's obsessed with the idea that Richard Donner's vision in the first movie was perfect, I'll deal. Spacey's acting will be the shining point of the film, and I'm continually happy they used a relative unknown for Superman (even if he is a bit of a pretty-boy).
All that said, I've been waiting for a great Superman movie to come out. And, I will be there opening day ready to cheer, clap, and believe a man can fly again.