Ask HN: The Twitter "stop retweets" button has gone?

Or is it just me? As indicated here http://blogs.bluegumtree.co.uk/vista/2010/03/06/127 there used to be a nice button that stopped retweets from specific people you follow, but it isn't there today.

It's very useful so I can't understand why they have stealth removed it I can't see any update information about it or anyone mentioning it apart from one post on Stackoverflow.

Does anyone know where or why it's gone?