Here's reasoning behind my bet:

First, Chinese plans for wind power are consistently ahead of schedule, and ridiculously so:

China had originally set a generating target of 30,000 MW by 2020 from renewable energy sources, but reached 22,500 MW by end of 2009 and could easily surpass 30,000 MW by end of 2010. Indigenous wind power could generate up to 253,000 MW.[58] A Chinese renewable energy law was adopted in November 2004, following the World Wind Energy Conference organized by the Chinese and the World Wind Energy Association. By 2008, wind power was growing faster in China than the government had planned, and indeed faster in percentage terms than in any other large country, having more than doubled each year since 2005. Policymakers doubled their wind power prediction for 2010, after the wind industry reached the original goal of 5 GW three years ahead of schedule.[59] Current trends suggest an actual installed capacity near 20 GW by 2010, with China shortly thereafter pursuing the United States for the world wind power lead.

It would be beating a dead horse to mention nuclear power and schedule in the same sentence.

Second, growth in wind power is extremely widespread.

On the other hand nuclear is extremely concentrated. Today US, Japan, and France alone produce more than half of global nuclear electricity - and they're not expanding much. All nuclear's hopes are about China, but China has little nuclear power, with very low utilization rates of what it has, and in fact China already produces more electricity from wind than nuclear!

And third, skaterpot's numbers are totally completely utterly wrong.

Wind capacity factors are rapidly increasing due to technological progress. Just 2005 to 2008 global average capacity factors increased from 19.2% to 24.5%. The problem was never "wind not blowing" - capacity is not installed based on highest wind velocities - the problem was getting adequate power from wider range of wind velocities. The real range is more like 30%-40% range for new wind farms.

Actual nuclear power capacity factor is 78% for 2008 globally. American nuclear gets 90%, but that's what you get from mature non-expanding nuclear industry, typical nuclear problem is entire plant being shut down for one reason or another, and such problems are concentrated in first decade of plant's operation. Nuclear will never get 90%+ capacity factors if it's rapidly expanding.

I'd be quite willing to bet wind overtaking nuclear in nameplate capacity around 2015-2017, but I'd need to double check all figures before putting my money behind this pet.

Assuming both are growing, we'd get capacity factors like 30%:75% - wind higher than now as most of these wind farms would be very recent, and nuclear lower than now as most of these power plants would have typical first-decade issues. This 2.5x growth can easily happen in another five years.