What forum software is compatible with WordPress?

[keress]

I’ve found discussion about Vanilla, and I’m wondering what other options there are for forums compatible with WordPress that can integrate with its database (so we won’t need to set up un/pw repeatedly for blog and forum use).

[Mark Jaquith]

Your best option (in terms of integration) is going to be bbPress, which is sort of like a sibling of WordPress. They integrate very closely by design. Anything else is going to be more work to integrate, so if bbPress meets your needs, I’d go with that. Else, line up your candidates in order of preference and start Googling “wordpress integration [name_of_software]” and see if there are any guides.