It is too early to know the specifics, but this will obvious impact:
(1) The five or so players on the UK roster this year that might have considered leaving after the season for the professional ranks (Jones, Lamb, Davis, Kidd-Glichrist, and Teague)
(2) The potential recruits for the 2012/13 season that have decided to wait until the spring signing period to commit to a school. With Jones, Lamb, Davis, Kidd-Gilchrist, and Teague all potentially returning, with three blue chip prospects already signed for UK next year, and with a highly touted transfer eleigible to play for UK in 2012/13... then minutes will be difficult to come by.
For fans of UK basketball... selfishly... I think that this move by the NBA Players Union is a good thing for the college basketball's 2012/13 season.