Joost executives have hinted at releasing a set-top box for their service, dropping hints such as "we can port our software to anything".
This would finally present a formidable competitor to Cable Television once Joost has more quality content (and there is already plenty). As said in an earlier blog post, Joost's lack of a fixed amount of content in a certain timeframe will lower the barrier to entry when it comes to broadcasting to a wide audience. Other technologies such as podcasting will also form competition (but in my opinion this will be to a lesser extent, despite having a leg-up now over Joost due to a much earlier head-start).
In a world where information vital to democracy is primarily controlled by a few media conglomerates that often have ties to political figures, a new video broadcast technology that lowers the barriers is extremely important. With Joost, it would potentially be much cheaper to run for the White House due to not needing as much funding for air time, which would result in more and perhaps better qualified candidates opening up.
Also comes the news that Apple is adding Youtube support to their AppleTV iTunes companion, which not only lowers, but completely blows away the barrier to getting a message out if the AppleTV becomes popular (or until Youtube comes up with more similar partnerships, which is likely).
It would allow small groups without the funding of corporations to get a message out quickly and easily. Lobbying, which I personally have doubts about, would become less effective as messages spread quickly through an interactive TV replacement.
The distribution of information is vital to a democracy, and never before has a tool as powerful as the Internet been available. Let's hope companies like Google and Joost continue to harness that power and wrestle control away from the media conglomerates.