The problem with this technique is you can't see subtle motions caused by planets that are small or far away from their star. Of course they are going to keep finding huge planets close in : that's all you can detect!
True enough, but the Jovian planets might have Terran-size sattelites.
The ameteur astronomers can provide key targeting data for the big 'scopes so as to not waste time scouring the heavens.