What happens with SimpleCart, now that Commerce is available?
SimpleCart has been superseded by Commerce. We no longer recommend using SimpleCart for new projects and will no longer release new features for it, but we do still offer support and will continue to provide security and bug-fixes as needed for existing sites.
At some as-of-yet-undetermined date in the future, we will no longer sell SimpleCart licenses at all and announce a formal end-of-life date.