If you take "illegal" at it's literal meaning - ie: "contrary to or forbidden by law" - then, no, commercial use of drones is not illegal, because the FAA has not (and can not) set "LAWS".
What the FAA *has* done is issue RESTRICTIONS. Those restrictions say that there shall be no commercial use of drones (presupposing that the continuation of that phrase is "... without you paying us a lot of money for our permission to do so"). Some judges are going to uphold those restrictions, some are not. And the FAA will still go after you if you are in violation of those restrictions and issue a fine. Again, whether it holds up or not will depend entirely on the judge.
But, also realize that restrictions are only the first step. The FAA will submit the restrictions to congress, who will then sort out how to build and enforce the actual law, I would imagine.