Now that vBulletin is adding social networking to make people's profiles more Myspace-like, they have become the second major forum script to do this. Invision had also added Myspace-style profiles to their script. So now people's profiles can have comments, a photo album, and skinning. They also have Myspace-like groups where anyone can make a group and be the moderator. I've also been working on a profile comments mod for phpBB w/ Categories Hierarchy so I'm interested to know if people like this kind of thing or don't think forums should mix with social networking.
I think it's kind of an inevitable road towards more Web2.0 ideas. Of course, some people will want to stick with "old-school" forum software that doesn't include all that profile and networking stuff...but that doesn't mean that it wont become popular.
I think it is a good idea for smaller communities, in order to communicate and learn, exchange ideas with each other, so I guess you should go ahead and create that modification for phpBB users! However; this modification may not be as wanted on larger communities due to the difficulty of running this kind of function, it may end up quite bad and I don't really believe many will have this function enabled (large forums, as in DP etc...) but only time can tell. - Meti