Google tells me 11.8 Million SMF installations and 26.5 million phpbb installations, so both is very popular. If you know PHP I would suggest you to take a look to the source code of each, you will see a big difference.
I don't want to advertise SMF, I only want to take care of this community and suggest you only not to use phpbb. Even if there are fast patches in the future, let's hope the hackers and bots will not know before these exploits.