Adds a tree node to the developer section, which allows access to your Robots.txt file from the root of your website. If you do not have an existing Robots.txt, then one will be created for you.
The editor contains basic validation for the Robots.txt protocol.
Version 2.0.1 definitely works with Umbraco v4.0.x, whilst version 3.0 is for Umbraco v4.5, and makes better use of the CodeMirror editor.
If you have a multiple website set-up and make use of the Sitemaps rule in your Robots.txt, be sure to use the Cultiv DynamicRobots handler.
Update: If you are using v2.0, then please upgrade to v2.0.1, as it contains a very important security fix.