Moro. OSM-wikistä poimittuna: "Brownfield is a land which was previously developed which is not currently in use. Brownfield land may be vacant or scheduled for future development."  
Sen sijaan "landuse=greenfield" sopisi paremmin kuvaamaan Näsisaarta. "The greenfield tag describes land scheduled for new development where there have been no buildings before. A greenfield site is scheduled to turn into a construction site at some point in the future, though the timing may be unclear - sometimes within decades or never." 