All you have to do is see that statement saying that the plant will be online 2008 to know that it isn't a nuke. Combustion turbines come on site as a number of modules to set on the foundations. After that, you run the piping and wiring and fire them up.
You don't need the containment structure or a fuel pool or the high security of a nuke plant. Natural gas is expensive only because oil prices are up. When they go down so will natural gas prices.
To some extent natural gas and oil move sympathetically with each other. Energy is energy.
But they are not direct substitutes and there is considerable independence in their pricing. You can't burn natural gas in a typical car nor can you burn oil in a typical natural gas furnace. Natural gas is typically most expensive in the winter during heating season. Oil/gasoline is typically highest in the late spring. A big difference between oil and natural gas is that for natural gas we are, for the short term, entirely reliant on our domestic (plus Canada and Mexico) supply which is in sharp decline. We have a very limited ability to import Liquefied Natural Gas (LNG).
As you look back through recent history you will see several episodes where natural gas prices both spiked and crashed and it had nothing to do with oil prices. Natural gas was hitting over $20 mmbtu at the California border during the California rolling blackouts while oil prices were quite reasonable.