Turns out all you need is some Scotch tape. For some reason I thought it was a more complex mechanism. Essentially the modern equivalent of the tab you used to see on VHS tapes to prevent overwriting. And similarly as I recall there were special holes to allow S-VHS to be written.
So yeah, all you need is a wee bit of Scotch tape. Takes all of 10 seconds and your SD card should be writable again.
One year later. Still awesome. Apparently in 2013 they chose not to shoot them all off at once. Their loss.
Seriously Google, you guys can’t update the Google Voice Android app with a swipe to archive feature on 4.2? You have Glass and self driving cars and yet a legitimate product that consumers would pay money for if you supported it languishes. Here’s what I’m thinking: I get a text message (not an MMS because for whatever reason that doesn’t work) I read it, and then I swipe left to archive with my finger on my Nexus phone. Seriously is it that difficult? How many people do you have working on this app? None? That would be my guess. Maybe one dude. I feel bad for that guy. Google Voice, much like Reader, is/was a great product that Google refuses to monetize. Please. For the love of God monetize Google Voice and at the very least update the app to Android 4.2 standards.