Once I asked for a way to know the date of the last update of a node. Maybe for a misunderstanding (I was talking about "submission" instead of the more correct "update") that proposal didn't become so popular.

What I was thinking about was something like [id://#####,date]. Having such a device, one could write a script that check for updates for the nodes he is subscribed to. Another possibility could be adding a smart link (e.g. [id://#####], last updated [id://#####,date]) in our homenode, so that we could check for updates simply logging in and looking at our homenode.

Update: We could also use a new tag, for example <update>, manually adding the date of the last update of the node. "Subscription scripts" could be written as easily as described above, I suppose.