Well in femlab 3.0 they have given models for working with mems and u can model actuators... their new version coming out in sep/Oct 2004 is expected to have more features and more MEMs based models.
I think they are working on coming out with a good generalized package to outbeat Ansys with a good interface with matlab (6.5 and higher) for extra PDE based model inputs.
Personally I feel FEMLAB has an adge as far as user interface and ease of use is concerened and I see no reason why it cant be used for mems. After all its all physics..