I'm fairly against steady state running, I think it's a very old and inefficient way of losing weight. The other problem I have with it is that it loses weight, not necessarily fat.
You'll notice that the muscles of a sprinter and the muscles of a long distance runner vary dramatically, and I think it's to do with what you use your body for. If you want to run long distances, it's easier if you're lightweight, and muscle presence isn't really required.
Definitely look up interval training for cardio (HIIT or tabata) , it's a lot more fun, it's more muscle sparing, saves you a heap of time, and causes you to have an increased metabolism long after you've finished exercising.
Also yeah, rowing and cross trainers are the best way to go for cardio IMO, otherwise setting up a circuit is also very good. You're using a lot of different muscles on your body, and you can actually experience strength gains in the early days of rowing.