Rob, I was going to ask the same thing. I was reviewing collaboration software for some clients a couple of years back. These tended to merge social media with project management. In one tool, which looked good, everything was a project. The last time I talked to the local rep for that company they were being redirected to a particular application area. I think the problem they ran into was with their project centered terminology they were lumped in with project collaboration and management products. Like Facebook, they were completely general purpose.
It looks like the vendors in the CAD space are going the same route. Make something "like" Facebook, but more specific. With this approach they can address security concerns while leveraging the social media idea.
Another answer to your question might be that the trend these days is for users to want their on-line experiences to be similar at work and at play. Considering the centrality of computers to our lives these days, that makes sense. How it gets implemented is another story.
Yes, I would imagine it feels foreign to most engineers, However, I have hunch that twenty-something engineers fresh out of college will get their hands on these tools and go, "Whoa, look what this can do!" Whatever vendor can wow the next generation of engineers may have a winner.
Rob, I think it's early on and way to soon to say these tools are gaining traction. I think with any kind of new technology, the software vendors are experimenting by pushing the envelope with capabilities that consumers are using in other aspects of their lives and seeing how they can make a difference with design tools. Some engineers will like the new way of working, others won't. But just like with any new technology, you've got to take some shots and see where it all lands. Years from now, I think social components will be a mainstay of every kind of software, but because it's new territory, it still feels pretty foreign to most engineers.
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