The Mac App Store can become a big security benefit, much like Linux uses repositories, but only if it becomes more popular.
Does Apple host the downloads for software after it is included in the store?
If not, this is a big deterrent for any developer that wants to provide free software to the Mac community because of the fee associated with listing software in the MAS.
This only adds to their costs which is not always supplemented by returns via donations.
But, I am beginning to notice many great free apps appearing in the MAS. It would be great if most of the options for Mac software were available via the MAS.
The MAS is no where near the "walled garden" of the iOS App Store, but it still has a balance in the benefits that it offers.