Mac App Store.
"One simple icon, a new addition to the Dock, means enterprise administrators can begin delegating to end users some of the responsibility for obtaining, installing and updating applications. Over time, the industry may find online application delivery and maintenance becomes the norm."
Sorry Erik, but as an experienced Enterprise admin for OSX and Windows, I can honestly say that one thing we definitely don't want is to give users responsibility for installing and maintaining their own software. We need our users to use the software *we* provide.
While Apple have done a good job on iOS of ensuring apps are free of viruses (or other nasties), that's only part of the reason. We also have rules on what software can be run on our machines (no games, porn etc), not to mention rules that require that we test any software we install *thoroughly* before we let users anywhere near it.
"No repurchase is required, no installation media must be tracked down and no license keys must be dug out of the back of file cabinets."
The think is that a large enterprise (such as the one I work for) will have a properly secure archive for any software they use, together with and keys/licences needed. This archive will also be regularly backed up. We have to buy volume licences for the software, so re-purchasing isn't normally necessary.
BTW, before you say I have a problem with electronic distribution of software, I actually don't. The software I manage at work comes from three main suppliers. Adobe, Autodesk and Apple. Apple are the only one that we currently get disks from. The other two allow us to download full versions of their applications (together with keys) via secured websites.
One question that I have as an admin is can I control who installs software via the App Store? While I know that my users are unlikely to find any Porn on the App Store, what's to stop them downloading and installing games, then playing them all day when they are supposed to be working?
TBH, I don't see how ANY of the features you mention will make things easier for the Enterprise admin, and I personally think the App Store will make things considerably harder.