So the power states that: Now, does this mean that I could, for example, Outwit an opponents Invulnerability, shoot them, they lose invulnerability (or are killed later in the turn).

Is Iron Man still countering a power? And, thus, can he use Super Senses?

I'd say he cant use super senses as he has countered a power that turn. But by the way its been worded...... you could ahve somthing

I would agree and say he could not use Super Senses as well. Even though one is not currently countered, he did counter a power or ability.

On the same note, could I Mind Control Iron Man, use his Outwit, and then he loses Super Senses?

Great question, it is very possible that he could still use Super Senses at this point, but I am not completely sure.

Invulnerability is still countered, even if the character gets knocked off that click. That's why if they later get knocked onto another click that has it again, they still can't use it.
So Iron Man still has a power countered by his Outwit and can not use Super Senses.

You could indeed do that. As long as a power is countered by his outwit, he cannot use super senses. It doesn't matter who controlled him when the outwitting occurred.

Can I use perplex and still use outwit as well? and do I get supersenses if I only perplex?

~THANX

Yes, as he has the use of both Outwit and Perplex you can use them each once per turn.
If you only use Perplex, Super Senses is still in play.