Scratch

When I was writing a message on the forums I noticed this "Adding Scratch Blocks:
To add Scratch Blocks to your post, type [blocks] before you start and [/blocks] at the end of the blocks.
Click a category below, then click the block you want to add. Then fill in the blank spaces in the text box above." Is this a new feature or has it been on scratch all the time? If it has I have never actually needed to do this.