What are some alternatives to the Mac App Store? I want something that will easily update all my applications. The Mac App Store doesn't do this with applications not purchased from the Mac App Store, I need something else. In addition, I would also like to be able to browse apps.
If you want an app-based app store alternative, then try Bodega.  It's a pretty good app that allows user to download/buy apps that existed before the app store did.  However, if that's not enough, you can always use different websites such as www.macupdate.com, www.iusethis.com etc.