I've never seen any other site do automatic polling of content from Wikipedia. I imagine that there might be some sort of issues with that, whether legal or technical.
However, linking to the relevant Wikipedia articles is an excellent idea! We strongly encourage members to create tag wikis for tags about which they are knowledgeable.
But the result of previous discussions about this on other Stack Exchange sites has been that providing a short summary (preferably in your own words) about the topic is far preferable to a simple link.
To get started editing tag wikis, click on any tag anywhere you see it. That will bring up a list of questions with that tag, and at the very top of that page, you'll see (for example) the following message:
The epistemology tag has no wiki summary, would you like to help us create it?
And because, yes, of course you do, click on that link!
All edits to tag wikis must be approved by another user with at least 750 reputation. And since, at this point, I don't think very many of us have managed to acquire 750 rep, that most likely means that you'll have to wait for one of the moderators to stop by. There's no guarantee when that will happen, but it doesn't hurt anything to submit edits and let them sit in the queue until they're approved.
Remember that you get +2 points for each approved edit, so that should be a bit of an incentive, as well.
I actually tried to "prime the pump" yesterday by editing a couple of tag wikis about particular philosophers. Here's a link to one of mine to help get you started in case you've never done this type of thing before.