I fear both programs are coming to a slow end. There haven't been any new Superman showcase volumes for a year (or a couple years if you don't count the World's Finest volume). Although on the Chronicles series, the Archives go a good 30 issues past where the Superman Chronicles are at, so continuing that line should be easy. Though given they were putting out two a year, but in 2010 and 2011 they only put out one each has me concerned.