The optimistic outlook is that this is just sabre-rattling by the Rams' owner as he tries to get the city of St Louis to pay for stadium upgrades or a new stadium entirely.
This is a pretty common tactic by big sports teams - they threaten to move, and no politician wants to be the guy that let Local Sports Team leave, so they end up extracting huge piles of money from cities that often can't afford it. By making their threat of leaving more credible, the Rams are hoping to get better concessions from the city.
You can see more analysis from that viewpoint on deadspin:
http://deadspin.com/report-rams-owne...d-l-1677488994