If you want to extend your WordPress blog with a open source forum software you’ll probably stumble upon bbPress. But there is a wordpress integration for MyBB too.
You need to choose the right tool for your business. The following post will compare MyBB and bbPress.
MyBB is written by the MyBB group, bbPress is made the WordPress way. bbPress obviously integrates much better with wordpress then MyBB does because it was written with that integration in mind. If you want to integrate MyBB and wordpress, you’ll need matching themes. bbPress is integrated directly with WordPress and you can use the WordPress themes. There are 72 free themes for MyBB but there are thousands of themes for WordPress.
Both bbPress and MyBB are extendable through plugins. MyBB does offer 182 plugins at the moment. bbPress has 229 plugins to offer, slightly more than MyBB.
bbPress documentation is more decent and well strucuted compared to MyBBs documentation. The auto updater of bbPress is much better than the MyBB upgrade process too.
bbPress has a good SEO support (speaking URLs for example), MyBB does need plugins to perform properly with search engines.
But there are benefits on MyBBs side too. The MyBB merge system allows easy migration from recent versions of bbPress, FluxBB, Invision Power Board, phpBB, SMF, PunBB, Vanilla, vBulletin, WoltLab Burning Board and XenForo. bbPress does not have very recent integration possibilities.
Another good point for MyBB is the performance of MyBB 1.8 compared to bbPress 2.5. A recent stress test showed that the page generation of MyBB is 40% faster than the generation of bbPress pages on a Ubuntu server with Apache and PHP 5.4. If you want to use PostgreSQL instead of MySQL you’ll need to pick MyBB too.
If you are switching from a different forum software to MyBB or bbPress you should probably use MyBB and the excellent merge system. If you want to run a huge forum with a lot of people you might also want to pick MyBB because the performance is far better. If you aim for easy theming and extensions and a great integration with wordpress you should probably pick bbPress.