While a wiki emphasizes content over form, many Socialtext customers need to customize look and feel. In fact, for Intranet use case, having branding consistent with other applications and the corporate style guide can be a usability enhancement.
With Socialtext, you can Skin your wiki. For example, take a look at this Skin on the Socialtext Customer Exchange:
Now, there is more than one way to Skin a Socialtext. Whip out your mad CSS skills and Web 2.0 gradients. Got a Socialtext skin you want to show off? Let me know.