I would agree with what has been said so far, but would like to add a bit.
I think that in general, the kenpo forms are less rigid and choppy, and more fluid than the typical Japanese or Korean katas, especially with Long Two and up. At the same time, they don't have as much flow and fluidity as you would see in many of the long arm Chinese systems, like Tibetan White Crane, Northern Shaolin, or Choy Lay Fut. In my experience, I think Kenpo really falls in between the continuum of Japanese or Korean vs. Chinese systems with regard to stylistic flow.
But at the same time, kenpo forms, many of which are made up of kenpo self defense techniques, tend to have more rapid-fire explosions of shorter range movement that the long-arm Chinese systems don't always have. A southern Chinese system like Bok Mei (White Eyebrow) might be more similar in that regard.