You could edit the second post in this thread with the update info and link to it from the OP for an example, though that might become more useful later on, for now you could probably fit all the info in the OP itself, so just editing that should be fine too.
It's your topic, so long as no rules are being broken you can do with it as you wish. :)
In fact @TwistedTwigleg implemented github gist embedding so you could just maintain a gist of the release log, paste the URL to the gist in your OP and it will automatically be rendered as an embed, so as long as you keep updating that same gist, it will remain up-to-date. ;)
