Yeah, that's pretty much been the line people have been taking since the first rumour ages ago pointed out they could be taken units of 1.
All fairness, the cats are angry. 3 Ws4 S4 attacks each. If you put 2 of them into a wizards face, the enemy has issues.
A) The cats are seriously quick with Mv8, swiftstride and vanguard. Depending on how away they started, you can quite easily face the possibility of losing your whole unit to a couple of 21pts cats. Thus, fleeing is not an easy option.
b) So, let's assume you allow them to charge. Cats are hitty. Let's take an empire wizard without gear: Average of 16/9 wounds. That's enough to make someone take pause. Even if you've got a decent ward save... you're still going to think twice about it. Worse, as the cats aren't champions, you can always get two against the wizard, unless he's on the flank.
c) You know what else Ogres have for character hunting? Sniping Maneaters with pistols. If they've already put a wound (or two on lords), sabre tusks can easily finish them off.
d) If at all fails, its still only 44pts. So is it really worth spending time on killing them?