The currently biggest are Enercon's E-112 (second batch) and E-126 at 6 MW, but the E-126 are probably suided for an up-rate (for comparison: the first batch E-112 were rated for 4.5 MW).

American companies are aiming for bigger: Clipper Windpower for 7.5 MW, while AMSC Windtec aims for 10 MW; but I suspect these aren't to be taken that seriously.

_{*Lunatic*, n.
One whose delusions are out of fashion.}