I don't think this has been posted yet and this is certainly first time I've noticed the following statement on US's "Airline partners award travel chart" (PDF downloadable from
http://shopping.usairways.com/en-US/.../usemiles.html). At the bottom of the chart,
Notes
1) Beginning January 1, 2013, award redemption in Lufthansa first class cabin is unavailable.
Sad, but on a more positive note, maybe this official communication will end all the repetitive questions about LH F posted here.