Thank you, @ragepeanut, both for your up-vote as well as your excellent comment and set of improvement recommendations! :c)

It is also a good sign that you were thinking along the same lines, as I like to think that good design is something that people gravitate towards. ^_~

Now, to your suggestions. :c)

Placing a post in multiple streams:

This is certainly 'possible' but I would suggest that only one of them is "free" Otherwise people might be inclined to abuse the system and create stream tags that are purposely similar to the top-paying terms.

In truth I'd also been toying with the idea of having an exclusion list barring the top 25 or so paying terms from being used - but then I figured - "Meh - if somebody wants to have a "life" stream then why not?".

fresh stream notifications

I am of two minds about this. If I choose to subscribe to @ragepeanut's gaming feed then I may not want to be bothered by notifications of a new stream on raging peanuts. ;c)

There 'are' other ways for a person to notify users of other content. Its kind of like how I advertised my other post in this post. Through allocating a section of the page - users who otherwise 'avoid' politics know that I posted a political post. Likewise I could have stated that I have a new "political stream category" and to go to my profile and 'Edit Following' to sign up for it if interested.

An alternative would be to upgrade the user interface to have users be informed by the user interface upon log-in that one or more of the persons they are following have new category (with a post in it). Clicking the notification could take us to a page dedicated to managing one's following, highlighting those with recent changes (and specifying the changes).

This way notifications needn't be committed to the blockchain. Such would be static.

Thank you again for the support and your suggested improvements. :c) Your enjoying my materials means a lot to me (I like your materials too - gaming-related especially).