Another selling point for Jerseys as a feature is I think its pretty obvious/reasonable it would be supporter only...and the more they do to spruce up that supporter package...the more supporters they get. New users would come in, see those Jerseys and think...wow that is cool I want one!! and then put their money on the table.
ONe issue though could be how its implemented and the quality. IF they were holding this off to ensure that when it is released its of a good quality, I could accept that. I think they should enlist one of the many volunteers that's been making banners for them....maybe offer them like lifetime supporter package in exchange for help making Jersey feature or something along those lines.