I confirm fellow fan Ines' gossip about the upcoming Klytämnestra in R. Strauss' Elektra. Karita will tackle the role for the first time at the Met in season 2017-2018. Just cannot wait for the occasion! The title role of Elektra will be sung by Christine Goerke, the Brünnhilde alongside whom Karita recently portrayed her very much acclaimed Sieglinde in Wagner's Die Walküre at the Houston Grand Opera.
Here is the link to the info of Karita's debut as Klytämnestra: http://classicalvoiceamerica.org/2015/04/23/houston-walkure-showcases-two-starry-sopranos/