I've never been out in Osaka as I prefer to go home and sleep... and if you go out in Osaka you have to spend the night there... no night trains to Kyoto. But everyone says there are plenty of great clubs.
...but here is night view, I took from my old workplace!! :)
There is now a guy organizing pub crawls around Osaka: See the link below.
The Ebisu-bashi bridge area was described in my Lonely Planet as bringing "to mind a scene from... the movie Blade Runner. It certainly is a splendid sight at night, standing on the bridge and looking at the facades of lights reflecting in the river. The people watching is fun here as all sorts of Osaka citzens congregate here!
Near the Hearton Hotel, I wandered after dark past the Osaka JR Station, towards the lights of the Hankyu department store.
There was, for some reason, a well-lit ferris wheel behind the store - perhaps 200-feet tall, so it wasn't just a gimmick!
But, time was short, and after 30 hours of being on my feet, it felt like time to get into bed, and I never got the chance to check it out later.
On the zone which faces the Kansai International Airport across the sea is Rinkuu Town which holds such commercial and cultural facilities as 256m high Rinku Gate Tower Building - the highest in the western Japan, Rinku Park with a beach paved with marble stones and a carved craft promenade, Rinku Papala for amusement, and Rinku Papilio.