True to Nintendo's word, SNES Classic units appear to be getting restocked at various retailers throughout the holidays. While stock is still by no means plentiful, GameStop has put up more SNES Classic units for pre-order today.
SNES Classics will ship on December 8. As of this writing the standard SNES Classic pre-orders (retail at $79.99) have sold out, but you can get a SNES Classic bundle for $124.99 which comes with a hardcover book.
Nintendo promised more SNES Classic availability than there were for the NES Classic last year. While SNES Classics are still selling out, it seems that there are more opportunities to try and purchase one. Even customers who couldn't get a SNES Classic on launch day seem to agree that the shopping process was smoother.