I just booked a reward ticket online and yeah, when I look up the flight on JL's website to select seats, etc. - no middle name.
Just last-name space first-name. My passport does show my middle name, hopefully it's not a problem.
No area to provide passport info online either... maybe it's too far out (Dec)? But most airlines I've flown let you populate that data in advance before online check-in... in fact some are downright pushy about collecting it early.