Enterprises don't need social solutions. They need good management and good application software. Everything else is a band-aid on the wrong wound.
It seems like every enterprise I work at has almost every gadget imaginable on their intranet: policies and procedures in a wiki, tips and tricks in another wiki, special domain knowledge in yet another wiki, an HR portal, project management apps, help desk apps, integration with email, integration with Office, integration with smart phones, etc., etc., etc. And how much difference does it make? Not much, I would guess.
People need access to exactly the information they need served up exactly as the need it to solve the problem at hand. This is called "good application software". And the need the resources, guidance, and direction to do the right thing. This is called "good management". Without these two, it's hard to get anything done. With them, those gadgets aren't really necessary.