Aikido is a mode where your goal is to manipulate the opponents tori so that he dqs. It takes much skill and though process when playing this made. Think about how to take you're opponent down, keep you balance, and keep from dqing yourself. Not to mention, if neither are dqed by the end, you still have to rely on points.
Judo is basicly hit the guy and hope something pops off then you win.
See the difference?