At a previous job, wikis made programmers management's markup bitch. We got bug reports like "Edit ${SALES/NOVEMBER} to reflect new figures from Marketing Marc" .. when Marc himself could edit the damn page.
For whom?
We IT people have a bad habit of thinking that a good solution for us is a good solution for everyone. From my experience in many enterprises, this is usually not the case.
First, a few numbers...
What I've typically experienced in enterprises:
IT people (programmers, analysts, admins) - 1%
indirect people (office, sales, management) - 10%
direct people (warehouse, factory, call center) - 89%
So a 1500 employee enterprise may have 15 IT people, 150 indirect people, and 1335 direct people. (The numbers may vary some, but you get the idea.)In an engineering firm or software house, the engineers and programmers are the direct people, but I don't really think of these types of firms as "enterprise".
Remember, no one earns anything until the direct people do something. Their production absorbs the overhead of everyone else, including IT.
Why do I bring up these numbers? Because I learned from a smart mentor long ago that solving your direct people's problems delivers value magnitudes greater than solving your indirect people's problems. Kinda like Willie Sutton robbing banks because, "That's where the money is." It's strictly a numbers game.
Back to the question at hand: your people, especially your direct people need the right information and direction to get stuff done. Good application software and good management have always been the most effective way of doing this. Sure, gadgets have a place and deliver some value, but they are generally not the solution to enterprise problems.
Like wikis, intranets, and all the rest, social media is just another gadget.
I really hate email in the enterprise these days. I can totally see where tools like Google Wave (R.I.P.) and Basecamp are coming from. Pity it will take most enterprises ten years to start using these tools regularly.