It's a GUI version of apt or rpm for regular users. That's why it rocks. It's not about the products on offer, but that you can download and install a bit of software autonomously.
Imagine: Gazillions of useful applications with a one click install for a new system - you dash through a department store of applications and say "this one, this one, not that one" - and it's all done for you.
Simplicity, and lots of it :)
I just want to know when we open source developers can start installing our software via it - imagine a sourceforge.net version, you grab the latest installs of Clamwin, Filezilla, gaim, and much more at the drop of a hat.