IGN had the chance to test out a first-generation Revolution development kit with no supporting software. From the article: "One thing is crystal clear from the controller-based development kits, though: Revolution will definitely operate as an extension of the GameCube hardware. These preliminary kits include only a wired Revolution controller, a wired nunchuck attachment and a wired motion bar... the controller and its attachments plug into existing GameCube development hardware."
IGN also mentions the Rev-mote's tiny size, calling it "much smaller than the remote that ships with the premium package of Xbox 360." They do say the controller does have a natural feel to it, despite its small size.
We're not sure how you can test a development kit without playable games, but at least they got their hands on the thing. Follow the link for full impressions.