I wouldn't mind at all if we signed M'Vila since I think he is a competent player who would add something to the squad.
However, I don't think we are in for him, or any other CM for that matter. We already have quite a few young players at CM - Wilshere, Ramsey, Coquelin, Frimpong. I don't think Wenger is prepared to sign another player ahead of them in the pecking order unless at a bargain price.
If the rumors about Giroud are true, then I think Wenger is quite happy with the squad, unless someone important leaves. Then he will no doubt replace him with an inferior player. 🙂