There are and have been quite a few ultra low fares over the last few months - valid through end of schedule. The smart MRer already booked/is booking now summer MRs - not waiting for summer to come along. Fares will go up - buy the loss leaders now.

My prediction is fares will be very high this summer on most routes but there still will be a handful of routes that have cheap last minute sales where lots of airlines compete and planes are flying too empty.