I just received an email from Apple that NewsRack 2.3.1 (formerly Newsstand) is now ‘Ready for Sale’, so it should be available shortly in an App Store near you.
This update does little more than changing the name, which I was forced to do due to a trademark complaint. Also, feeds that use basic authentication should work better in some cases.
I’m still working on resolving a specific problem some users are experiencing with Google Reader sync, so another bugfix update will probably follow shortly. In the meantime, I recommend to re-enter your password in NewsRack’s settings if your feeds don’t refresh.