It's probably permanent, we can't go back to SMF 1 due to a major exploit that got a bunch of accounts hacked
Badspot tore it to pieces anyway due to other, less major, exploits and abusive features, so good riddance
Here on SMF2, avatar uploading works again, we have tables back, there's no more page stretching, etc, so it was worth the move and having to deal with this default theme, whether or not it's temporary