The Great Intelligence did mention The Valeyard is one of the names by which the Doctor will be known by the end of his life, and we know that The Valeyard is the final incarnation of The Doctor. The sixth Doctor did meet him and The Valeyard so Matt Smith's Doctor would know about him. After The Trail of a Time Lord, The Valeyard did survive.
Watch the new episode and I thought it was okay. Didn't care much for the story, felt like just like too much of a setup. Not that I'm not interested in finding out who the new big baddie is this season. Although I was a bit creeped out at the outcome of the Kyzlet.