Well theres always facebook groups i guess. I guess Bioware wants this to be more so of a forum site and not so much as a social site any more
... and that pretty much hits the nail on the head really; it'll reduce bandwidth and hosting costs a little.
Then again, I've never joined a group - only ever accepted 2 friend requests and have never considered this really anything more than a forum on which I use one of my half-dozen or so Internet identities. As I see it, however, the thing that brought people together, to make use of the group functionality in the first instance, was a shared passion for BioWare games (Mass Effect, Dragon Age, whatever - think I joined BSN with NWN2 or maybe DA:O) ... where else are you going to get that sort of "first step" where you'd make those friends originally?
On the bright side though - those of you who've got groups, you could migrate them to G+ and set up a circle there I suppose - or Facebook ... or get old skool and start an IRC channel. I doubt this will lead to an off-topic apocalypse across the forums (unless it's done to make a point), more likely something of an exodus. If it all gets too quiet and boring after that though - I suspect many other random forumites, like myself, will just move on.
I've been doing this crap for about 15 years now, I was a community moderator on Fortunecity back in the day - this won't be the first time a community has collapsed due to a change in policy from the organisation running it - and it won't be the last. You move on and take your friends with you ... or not, either way.