You can update Twitter via plurk but there is no way you can update plurk via Twitter. It might be with plurk’s close API. Though, there are a lot of 3rd party applications (ping.fm, posterous, hellotxt, others) where you can update plurk without logging in to plurk website. But it would be great to update plurk from twitter.
The syndeolabs, a Philippine-based group of software developers, probably find that ‘hole,’ and so they created Mechanical Plurk – a third party application which lets you update your plurk account using your Twitter account… If only it is not in hiatus.
Hopefully it will be up soon from it’s slumber.