Me, I like Namba. It's the central district in south Osaka and generally rowdier and less buttoned-up than the somewhat higher class Umeda in the north. This trend continues toward the south with the Tennouji district, infamous for housing some of the poorest and most crime-ridden areas in Japan. Of course "most crime-ridden" still means I'm safer there than I'd be in central Stockholm.
Namba's not beautiful; nor is it old and historical. But it has more life and more happening than any other place I've ever been. I can happily spend a whole day just walking somewhere in the area, not even bothering to bring a camera along. Mill with the people in Doutonbori; check out the weird fashions of Amemura or the arty galleries, restaurants and cafés around Yotsubashi (our favorite Chinese place recently closed, unfortunately); shop for electronics, parts, robots, toys, power tools, audio equipment, manga and DVD in Den-Den town, or any cooking equipment and restaurant supplies you can imagine along Douguya-suji; or check out the clubs and bars of Shinsaibashi if you're in that kind of mood.
Namba in Osaka is perhaps my favorite place in Japan. The area can change dramatically with just a few steps down some street. It's not beautiful even in the best of times, so bad weather is not a problem when you visit.
Host club host going home at dawn. Namba is home to a large restaurant, club and bar district with places ranging from the stodgy to the disturbing.