http://www.freerepublic.com/focus/f-news/977257/posts
The justices did not close the door to such action. A winning brief will explain why a member of the legislative branch is a "public official" within the context of mandamus. It will also have to explain why this is a narrow case, i.e. why granting mandamus in this instant will nt lead to constituents suing their elected representatives every time they dn't like what is being done (which seems to be the court's concern).
The Texas Supreme Court has left the door open here, and the first person to file a brief that backs up the above propositions with good case law and arguments will have a good shot at success.
Since only three Justices noted that the dismissal was made without regard to constitutional issues, that sort of implies that the other six Justices don't agree.