Do you really need to be nannied?
Go on to versiontracker and macupdate and you'll see lots of comments. If an application is good or sucks there will soon be comments to indicate.
Apple need to sort out its AppStore. Its way too easy for a good application to get lost amongst the average / crap applications.
Not everyone knows about MacUpdate, we know, general average Joe doesn't.
The Apple Downloads page (that has a link under the Apple menu).
It would need to be revamped, there'd need to be a verification/validation process, and there'd need to be a bunch of other things done, to make it more like the iPhone app store. But, it could be done.
And, as long as no other changes were made to Mac OS X, you could still download via dmg, via source code, etc.
It would just give you the option for one stop shopping, one stop automated updates (versiontracker, last I checked, wont tell you which of your installed apps have updates, because versiontracker doesn't actually know what you have or haven't installed, or installed and then later deleted, etc.), easy search that doesn't mix in all kinds of "seems related, but isn't even a Mac app" results, etc.
Not saying it would be perfect, but it would make some things more streamlined and integrated.
I see the Apple Downloads section, but it is more of a mess than a help. Yes, a more streamlined system is what is needed.