What about putting the rating thing below the last comment, instead of above the actual content of the post. You're asking us to rate the thread, but we can't rate something we haven't read yet. And in order to read it, we need to scroll down the page, likely reading the comments as well as the OP (i.e. the whole "thread"). Then in order to rate it we now have to scroll back up to the top.
Why not solve two problems: move the rating thing down so it's less obtrusive to those of us who don't use it (and also to those who do), and also so it's better-placed for the convenience of those who want to use it to rate the tread they just read through.