Is wind growth stopping, and hurting wind manufacturers - can we see this in the stock market?

Yes, partly.

GE, of course, has seen it's stock fall, but that's because of their finance arm. IOW, they're not a "pure play". Vestas is the other large player: I took a look at them, and they seemed to be doing
pretty well especially for a large, capital stock manufacturer. Such manufacturers are always hit hard by the stock market in a recession like this. They still seem to be profitable - and orders are increasing a bit from last year. It's not clear if world wind installations will be as high as last year (that was also affected by the US's delay in extending the PTC - that killed some early 2009 deals), but they'll still be quite healthy from a longer-term point of view.

Will wind grow in a free market?

Yes, with regulations: CAFE, cap and trade, feed-in tariffs, and utility market share requirements are all compatible with free markets - they just provide guidance to the market.

Can renewables compete with dirt cheap oil and coal ?

Not until recently, when better regulation arrived, and sparked dramatic growth in the market,which produced economies of scale, new engineering, and thus much cheaper prices.

Now, let's be clear on wind's competitiveness. Coal is the big problem: old, dirty plants are dirt cheap. They will be for 50 years, if we continue to build and use them. We don't need wind to deal with PO, we need it to deal with climate change. We may or may not decide to aggressively replace coal with wind, but it's useful to know that it wouldn't be all that expensive: just $2T, less than the cost of a lot of other things: Iraq war, the US finance bailout, etc, etc. Of course, wind has a payback, unlike war, and parts of the finance bailout - in the long run, and counting all costs, it's likely to more than pay for itself.

The main problem with energy isn't technical, it's political: the 20% of the workforce who would be made obsolete will fight it quite hard. But, it's useful to come to consensus that this is the case, and that the technical barriers aren't that big a deal.

What about oil?

The short term problem isn't electricity, at least in the US. It's more moving to PHEV/EV's, and we are, in fact, doing that. The Volt will be in large scale production in 2 years (GM is building it's future around it), and others will be as well.

What if we have a sudden oil shortage?

We have more than enough energy to build new vehicles. For that matter, we can carpool and telecommute during the transition. We really can. I'm often baffled by the lack of awareness of the potential of carpooling: the US could cut it's oil consumption by 25% in 3 months, if it chose to. It would be inconvenient, and require an emergency to do, but everyone would still get to work.