If you didn't see the interesting article in Friday's WSJ, London's National Theatre is entering the HD moviecasting market with four live* play transmissions beginning on Thursday. The list of US venues is here.
Unfortunately this first show -- Racine's Phèdre (in the Ted Hughes translation) starring Helen Mirren -- is already sold out in its only same-day venue in New York City, but both Walter Reade and BAM will show it delayed in July.
Incidentally, the Met is offering summer reruns of its own shows beginning late August in the Lincoln Center plaza.
(* Live, I believe, in Europe, but delayed until the evening here.)