ScreenJelly is very cool! Take screencasting w/audio and Twitter and merge them together into one big event. No installation and everything is done via the browser.
Authentication is oAuth, so security isn’t a concern there. Once the recording is complete, a maximum of 3 minutes, it is ready to tweet and share across other networks and even email (this facility is built in also).
I did a test run and was quite impressed. You can mark videos private and not tweet them if desired. It actually records them locally first using an applet and then uploads when you authorize the tweet. It uploaded quick and once done allowed me to see the number of views and any comments left about the video itself. For sharing they use their own URL http://screenjel.ly/ which helps brand it further.
I think I found a new tool I can use from any machine for a quick screengrab and commentary. A view of my profile on the site shows all my recordings and my last 3 tweets. Once you click to watch the video you can retweet, reply to me or even share it yourself from the interface.
There is no ability to brand the video unless you ran your logo in the corner of your screen as it captures whatever you are showing.
UPDATE: It also seems you automatically follow them on Twitter which I did not see mention of anywhere. If it is there, I apologive but it was not apparent and I don’t like auto-follow settings.