I created an account on Newsgrounds to try out that site for getting feedback on my Unity games.
The site is quite nice overall and has the ability for you to upload a Unity game directly so people can play it without downloading. There is a nice "under review" period for each game which induces people to rate the game and give feedback, so I think this will result in getting some fairly quick feedback.
I've uploaded Chuckie Egg as a first attempt and it made it through the "under review" period OK.
I'll see how that goes for a few days and then consider uploading a few more of the Unity examples. This wont work for the Python games so I still intend to release those on Pygame.