EMD International has recently published a new report. 

This report provides a status on costs of wind energy projects at the end of 2009 including O&M costs based on statistics gathered from more than 250 operating turbines in Denmark with a capacity of 600 kW and up. The figures are applicable for Danish conditions; hence the findings of the project cannot be directly applied in other countries. The report contains data for both on- and offshore projects.

You can find the report her and read the english summery.