The intranet in the workplace today is evolving albeit at a slow (sometime very slow) rate. I remember back in the Evolution days we used it for plainly common urls, storing common forms / word / excel docs etc. that everyone would need to edit, timesheets etc.
Then we added a few CGI apps like a serial generator for Sound Studio Pro and some other legacy products. Then pictures from the company parties, outings, - when an employee passed a driving test we’d go out for a company curry - stuff like that.
Going to other small/medium companies you’d see similar intranet systems. Then for larger institutions like Trinity Laban, you see things like a huge Sharepoint system to deal with. Students and Staff still communicate via email. Things like sharing photos from parties and even of performances are limited to the realms of Facebook and email.
Where/how Social Networking can fit
By no means the only way. Social Networking can solve many more problems than described here. Here are some things social networking can help.