The new HDMI 2.0 spec should(?) be in receivers by next year, current HDMI chipsets can only handle 4K video at up to 30Hz. I'm sure that AVRs with "full" 4K capabilities are forthcoming.
ht Panasonic TC-P60ZT60, Monitor Audio: Silver RX6, RX Centre, Radius 90HD; Martinlogan Dynamo 700, Marantz SR5006, PS3, Oppo BDP-103D
2ch Marantz PM8004, Sony BDP-S1000ES, JVC T-X3 tuner, Monitor Audio Silver RX1, REL T3, Apple TV, Peachtree Audio DAC•iT
lr Panasonic 50ST60, Sony BDP-S5100