thx for the promotion
the most important aspect of getting "great abs" involves your diet. if your bodyfat isn't low enough, it doesn't matter HOW much you work your abs if there is too much fat on top.
and there is a lot of controversy about abs.. just with the biceps, there is essentially only one type of movement.
and hip flexor exercises like leg raises are worthless because they target an area called the psoas, which is useless.