Yes, MW is a unit of the rate of energy production, MWh is the amount of energy produced (e.g. 1 MWh is the energy produced in one hour at a rate of 1 MW). Nevermind - but for future reference, I also note that mWh would not be Megawatt:

1 mWh = 1 milliwatt-hour = 0.000,001 kWh
1 Wh = 1 Watt-hour = 0.001 kWh
1 kWh = 1 kilowatt-hour
1 MWh = 1 Megawatt-hour = 1,000 kWh
1 GWh = 1 Gigawatt-hour = 1,000,000 kWh
1 TWh = 1 Terawatt-hour = 1,000,000,000 kWh

(Sorry for the pedantry, but I am both a chronical nitpicker and an ex-physicist.)

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