I like the app for providing access to different games from one place. Besides it saves games data on a remote server, so that when you reinstall a game you have your progress saved.
This application is made for those who prefer to buy games via the Internet, download them directly onto their computer and not to worry about moving the game saves to a new machine. Of course some people might find it not that convenient to have access to your Steam account from the game, but in fact it isn't that bad.
I totally hate Steam, I hated the very idea of it as it first appeared back in 2003. Of course, I know all the arguments that it's very convenient when you can buy a game you want per Internet, downloading it onto your computer without further delays, but it's just fantastic, how much this software can spoil your gaming pleasure, just crashing all the way you play and entails crashing of the game itself. It is just so gross...
There is a Download button on the page, here is the link: http://macdownload.informer.com/steam2/download/