Hiya Tim. Personally, I don't think that jump rope is particularly good for intervals. Main reason is I'm not very good at it!! I find that I catch my feet with the rope at least once a minute if not more so, the stop/start nature doesn't lend itself to the periods of intensity required for intervals. If you have good technique and can skip at a high intensity for prolonged periods, it would be as good as any other kind of cardio for intervals.
As general cardio though, it is excellent.
Hope that helps