Not to my knowledge but the nVidia Shield TV (more expensive than Nexus Player but better hardware and still runs Android TV) lets you stream from a PC running a supported nVidia GPU.
I've been very tempted to pick one up even if I don't use the game streaming function too often. It'll be a nice bump up from the Chromecast and I'll be able to occasionally fire up a game on the PC and play it on the living room TV (albeit at 1920x1080 instead of 2560x1440)
As ixnu mentioned - I use the Moonlight Android app (http://moonlight-stream.com/) paired with Geforce Experience running on my Windows box (Geforce GTX 750 Ti video card) for Steam games.
To be honest though - my Moonlight streaming experience hasn't been as smooth as using a device that can actually run the Steam client (Linux/Mac/Windows). But Moonlight is still really cool.
I've been very tempted to pick one up even if I don't use the game streaming function too often. It'll be a nice bump up from the Chromecast and I'll be able to occasionally fire up a game on the PC and play it on the living room TV (albeit at 1920x1080 instead of 2560x1440)