Can plasma turn garbage into a positive?

Superheated gas incineration

While CO2 emissions from autos seem to get all the glory in the war on global warming, methane is even bigger problem. To solve this issue, many are looking to plasma as a new way to incinerate garbage, which converts organic garbage into pressured gas that can power a turbine. Additionally, the process also creates steam, which can also be used to further power turbines.

Compared to conventional incineration, SCIAM states that plasma results in far less emissions. More important, it reduces methane emissions from landfills.

Of course, methane can be captured at landfills, and some claim that that is better than any emission-spewing incineration.

Is plasma a legitimate alternative energy, or just the lesser evil? Does it matter?