Most bbPress and WordPress plugins for BBcode rely on the Pear PHP class which is HUGE and SLOW. The big problem with that is it has to execute for every single post, every single time a post is displayed, because the post is stored natively in bbPress with the BBcode intact. An active forum can get overloaded.
This version is less than one tenth the size and executes much faster. It also takes into account that bbpress does the rest of the parsing. Users may mix bbcode and html in the same post.
If "Allow Images" is installed, the [img] BBcode will also work.