Hi,
it would be a lot more than an asset store, it would be completly integrated in your workflow.
you search an action on the playmaker action browser, and it would list as well what it found on the actions server, that is not yet in your assets, then you could download it instantly and have it in your state straight away! it would require a custom action browser of course, but nothing impossible here.
no more searching on forums, it's all there where you want/expect it.
bye,
Jean