I found that location services still impacts my battery life a little bit. But I love being on 5.01. I use folders (from the 4 + updates) for so much and the multi gestures on my iPad 1 are great. I don't really know how long my battery lasts since I put my iPad to sleep when not using it.
Other tips include setting the mail app to fetch mail less often and turning brightness down. If you haven't done it, you should reboot the iPad too.