I do not know how it was in previous versions, but in 2010 does not happen,
ie (setq ss1 (ssget)) works, but the Select Objects: ss1 - no, writes *Invalid selection*
I've updated my previous posting. Now if a command is inactive, it will select everything (for pickfirst) and if a command is active, it will store the chosen selection set as SSS (variable) and print to the command line as "!SSS ". The selection set will remain stored as SSS, which can be called at anytime with "!SSS".