Ok, this is a bit of a weird question. But here goes: Im a fairly cut guy as it is. I dont do any cardio at all except like 5-10 before and after a workout, but its a walking pace. I do no ab training at all. Now to make you hate me, i have good abs, and am vascular with little fat. To make you hate me even more, im pretty muscular too :). Ok, now that youve stopped reading in disgust, i want to know if you think i should do anything for my abs and/or cardio. In the summer i work in landscaping, so i think that covers cardio, but as for abs, should i just let them be if they are ok, or should i do some ab training? I want nice super toned abs, and i guess my real question is, can i get sweet abs doing ab training alone, or is it gonna take cardio as well? If so, tell me what to do, and if not, tell me what to do as well…if that makes sense 
Getting “sweet abs” is more about diet than training. As you stated, naturally lean guys can sport a good six pack even without direct ab training. Obviously, though, adding in ab work would make them even better. (Read my “Evolution of Ab Training” article for tips.)
That aside, of course you should be training your abs, not just for visual appeal, but for functionality, safety and balance. Read Paul Chek’s stuff at T-mag for more info.
As for cardio, I wouldn’t overdo it. When I used to do landscaping I found I had a hard time adding weight during that time. That’s probably enough for now. If you read my stuff at T-mag, you know that my main beef with cardio is when people use it excessively instead of focusing on their diets. It’s not evil, just misused in many cases. That being said, I really like Berardi’s idea about using light cardio work to help with insulin resistance and Dave Tate’s ideas about GPP. In fact, I just got back from a tire pulling session. Good stuff, man.
i agree with Chris. Since you’re already lean there is no reason to throw in cardio. However, if you want larger ab muscles then you’re going to have to ab work. Read the ab articles by Ian King on the mag too and start training them first in your workouts. You’ll notice a huge difference in a month if you stick to it. Plus, your core is really important for stability, balance, and strength for other exercises. There’s no reason you shouldn’t be doing abs.