I have downloaded and installed the "graphene shortcodes" plugin without problem on my wordpress3 web site (rycw.be) and the features seemed to work.
However, this plugin spoiled my home page with unwanted side effects on the text layout (even outside the text using shortcodes).
Reversely, applying simple modifications elsewhere had side effects on the text using shortcodes.
I could not rely on a stable behaviour; it looks like the wordpress3 editor is competing with the shortcodes plugin.
After spending some time trying to fix this, I decided to disable the shortcodes plugin and to look for another text enhancing solution.
I sincerely wish I could go back to version 1.9.3 as I found theses shortcodes interesting.
Maybe the plugin will be improved in the future, but it obviously requires further debugging.