http://www.nsf.gov/pubs/2010/nsf10073/nsf10073.jsp?org=DUE
<LI>"April 4, 2011. Announcement of supplemental Nordic Research Opportunity awards." - its the last bullet under proposal deadline
FYI - you all should know, i checked the info on the new nordic fellowships and they are supposed to be announced on monday. since only NSF fellows can accept a nordic fellowship, it seems like they'll announce all the fellows then too.