I would say the original post is solved with respect to the current Lithium functionality. You can not vote on your own idea.
Toby had requested from Lithium that an enhancement (or fix) be made to add the automatic up vote for the original poster and/or to allow the original poster to add an up vote.
Since Toby is no longer with PTC, I don't know if Jaime Lee is pursuing this concept or not.
If you would like to add feedback for Jaime, you can do so at the link below which is the new area for community complaints/ideas/enhancements/fixes, whatever you want to call it.