Kamen Rider Dragon Knight just aired a preview episode on CW's CW4kids block. It won't start airing regularly until January 3, where it'll reair the first episode and go on from there. For a first episode, it did a good job keeping me attached. It didn't go into plot much. That'll likely be explained more in the second and third episodes. The first one was good at hooking people with the action and wonder of what's going on.
Has basicially three fight scenes: one at the beginning, one with grunts, and then one with an episode monster. The action in the fights were well done, both in and out of costume. I couldn't tell if the main actor Stephen Lunsford, who plays Kit, was using a stunt double, but Wing Knight's actor Matt Mullins seems to have the martial arts skills to back up his acting. That's something I miss about Power Rangers.
The theme song is decent. Not grating to the ears like some others I know (looking at you, Operation Overdrive). The intro does show all of the riders, which I thought was odd since I guess they would be slowly introduced throughout the series.
Dragon Knight is the American adaptation of Kamen Rider Ryuki and is produced by Adness Entertainment. Not having seen Ryuki, I can't judge it as a comparison. However, I think it does well on its own in the American toku market, hopefully giving Power Rangers some much needed competition.