I am looking for a reputable Q&A forum vendor. Any suggestions?

[gravityseo]

A vendor who has high domain authority;  with a platform that is social media integrated, can provide a backup database, has advanced navigation options, is designed to be SEO savvy among other things...

And basically anything that I can make look similar to the SEOmoz Forum!

[BradBorst]

If you are looking for an open source solution, I recommend phpBB (http://www.phpbb.com/).  We have used it for a few years for our forum and I'm happy with it.

[AdoptionHelp]

In case you're asking about how to build a Q&A site you will likely find this link useful:

http://engineeredweb.com/blog/09/11/building-stack-overflow-clone-drupal-part-1

I also built http://www.adoptionexperts.org in drupal in about 3 days. Its a fairly simple thing to get set up, hard to seed with good content.

[RyanKent]

If you are seeking forum software that can meet your needs I highly recommend XenForo http://xenforo.com/

Facebook automatic logins and likes are integrated into the platform along with twitter widgets. SEO is integrated into the base software also with features such as friendly URLs, thread id's which allow threads to be moved without breaking URLs, HTML 5 data embedded into breadcrumbs which Google reads, and more.

I am not clear on your "provide a backup database" request. Any forum software is database dependent, and you will want to back it up regularly with a simple script. I am also not clear on "advanced navigation options".

I was in the market for forum software in January. I used phpBB previously and was very unsatisfied, but then again it was a free forum solution. I investigated IPB, vBulletin and a couple other solutions thoroughly and took the risk of going with XenForo as it was a new company. I couldn't be happier, and purchased another license this week with plans to buy more in the future.

[gravityseo]

Thanks for the helpful advice everyone.  Xenforo looks like it has everything what we need.