Perhaps this is too late catwood, but since few of the respondants seem to know Osaka well, I can report that in my two long visits, Osaka was surprisingly good fun -- it is much more old-fashioned than Tokyo, and people, gays included, are friendlier, warmer, and louder (like the midwest vs. New York -- and I lived in both). Utopia and the other sites given in posts list bars, the two I like are in 8-23 Doyama-cho, especially Live Physique.
On the other hand, Tokyo has those wild saunas and boxes...