Interesting comments from the PBwiki founder and a good explanation of the difference between between UGC wikis like Wetpaint/Wikia vs. tools wikis like Confluence, Google Sites, and PBWiki.

Quoted: As the founder of PBwiki, I can say that we don’t see ourselves competing against Wikia or Wetpaint at this point - both of them are media / user-generated content companies. We’re a tools company. We’re sort of in the same space as Atlassian Confluence, Jive Clearspace, MS Sharepoint, and Socialtext, but we’re the only serious *hosted* wiki solution for businesses out there. And we host more business wikis than anybody else - 30,000 businesses, in fact, including over a third of the Fortune 500.
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This leaves the remnants of Jot (i.e. the dramatically scaled-back Google Sites) and not much else. Jot seriously would have been our worst nightmare if they hadn’t been bought and shot in the head. Joe had a killer team.

How the Obama campaign is using wikis (and other Web 2.0 technologies) to organize volunteers.

Quoted: That the Obama campaign is so tech savvy and so open to using social software is unsurprising. They have run one of the most comprehensive online campaigns in recent memory -- perhaps ever -- generally outperforming opponents on nearly every social network or social media site, and according to a recent post from Ning's Marc Andreesen, Obama has long been very interested in social networking and how it can affect politics.

I am pretty impressed with this. We have begun using it at Faves (instead of Sharepoint and instead of other hosted Wiki offerings). Aside from your standard Wiki features it includes:
- The ability to upload and version files
- Easy integration with other Google applications (duh)
- A flexible list type
- Web parts (well, Google Gadgets)
- Two-Column view

From Google's perspective, I think it nicely ties together all their "Apps for your Domain" offerings.

Sharepoint does have many features, however, that are missing from Google Sites.

Quoted: We’ll explain how Google Sites works, below. The idea behind Google Sites is to provide you a tool that lets you easily build intranets, project sites, classroom sites, employee profiles or whatever else your company needs to better organize the data they wished to put online. “Click a few buttons and have a huge swath of infrastructure taken care of,” Google Sites senior product manager, Scott Johnston told us. Note: He’s the former vice president of products for JotSpot.

Another hosted "enterprise" wiki.

Quoted: Enterprise wiki software for sharing and editing content, online collaboration, knowledge management, document management, file sharing, and more. Used for open source and commercial applications. Free 30-day eval.

pbwiki's success illustrates that companies are becoming more comfortable storing their 'internal' data on externally hosted services. I think we will start using it.

Quoted: Instead of having your documents and knowledge scattered between multiple computers, your PBwiki offers one central place to store files and collaborate – so everyone on your team can access what they need, from any location.

My friend works here. Wiki technology meets investing. I like the bulls and bears tabs.

Quoted: The largest investing wiki with research on hundreds of companies, investment concepts, and more.

Quoted: Free book summaries that anyone can edit! WikiSummaries.org provides free summaries of books, plays and other written documents. This complements Wikipedia, which is already an excellent source of information on authors and brief book summaries.

I know lots of us own HTC phones. Note: It's hosted on wetpaint.com

Quoted: Hi everyone and welcome to the HTC smart phone Wiki. This is a community site, a place for smart phone and Pocket PC users to post tips, tricks, ideas, rants and raves. But most importantly its your site. So please join HTC employees and partners in contributing to this site.