Some of the contestants are voted out in tonight’s show – but others get the benefit of the experience of some previous Idol survivors, as previous contestants show up to mentor the new folks. And sing with them, too, as part of this final-season stroll down Idol memory lane. Note that, for this final season, interactive home voting has been removed from the equation for this Top 24 elimination round. Idol wants to do everything it can to stack the deck with someone worthy of bookending the Kelly Clarkson-launching opening season – and if that means cutting viewers out of the mix for another week or two, that’s show biz.