They didn't! Too much Christmas kaos, and not enough time.
There was another person I asked about 'forums' and after finding a random forum on the internet they said a forum looked sorta like google groups which they did occasionally use for work. I checked out google groups for a bit, and I'm not sure overall the quality is as high as forums are. I found a few 'google groups' that were actually old 'use group' feeds/content filled with low quality spam.
Highly doubt it. For some reasons, solutions like XF, IPB, vB, phpBB, etc. just are rarely, if ever, used for large corporations. This isn't always the case, and don't ask me why it isn't as widely used as it perhaps should be. But you'll find things like Jive and Lithium powering some of the largest corporate boards, if they aren't alreayd using a totally customized solution, which is oftentimes the case.