We've discovered several more vendors since we first looked at the enterprise questions and answers space earlier this year. It's a young market, but one that's heating up quick. There are pure Q&A vendors like the ones we mentioned before, and several other social platforms have added Q&A features to existing products.

Here's a look at nine companies that are trying to improve knowledge management through Q&A software.

Pure Q&A Vendors

MindQuilt

MindQuilt is an early entrant in enterprise Q&A. Founder Daniel Kim says the company's main competition is actually not any other product - it's inaction. He says the company's customers don't ask about Opzi or Quora - instead the question MindQuilt is different from a wiki.

And how is it different from a wiki? Kim says that most non-technical users don't know how to contribute to a wiki. Also, it's difficult to create and change a wiki's structure. MindQuilt, he says, provides an easy interface and a simple structure for knowledge sharing.

MindQuilt is promoting its routing features and game mechanics incentives key differentiators.

Opzi

Opzi is set to launch next month. According to founder Euwyn Poon, Opzi is moving towards wiki format that emphasizes knowledge management.

One thing the Opzi team is focusing on is how to harness users' existing habits. There already a number of ways employees try to get their questions answer - such as asking the person sitting next to them or sending the question to a mailing list. Poon doesn't think it's a good idea to fight those ingrained habits. It will be interesting to see what the company comes up with.

Qhub

Qhub is less enterprise-focused than the other vendors on this list. It's designed for business that want to build hosted Q&A sites. Typically, these will be public facing. It's the Blogger or WordPress.com of Q&A sites, and is the sort of thing you'd add-on to an existing site or blog.

Some companies are using it for customer service, which puts it into competition with companies like GetSatisfaction and UserEcho, which both include a Q&A feature.

Enterprise Products with Q&A Baked-In

Bloomfire

Bloomfire differs from all the other vendors listed here in that it is a video-oriented solution. In this way, it could cross-over into our YouTubes for enterprise list. More specifically, Bloomfire is a social learning suite. Its customers include The Kellogg Company, Overstock.com and Lifesize (a division of Logitech).

One of the goals of Bloomfire is to develop learning resources that answer multiple questions. "If normal Q&A sites are a rifle, we're a shotgun," says CEO Josh Little. What he means is that using a typical Q&A tool you normally get a very specific answer to a very specific question. Bloomfire wants questions to serve as the springboard for users to share much more knowledge about a subject than a single answer. It prioritizes creative presentations that answer a several questions about a topic.

The use of video is one way to facilitate this. Although users can leave textual answers to questions, Little says most users are more comfortable just turning on a Web cam and speaking naturally than they are trying to craft a well thought-out written response.

MindTouch

MindTouch, an enterprise wiki geared towards developers crafting documentation, has a Q&A feature built-in. You can see it in action at the Complete Android Guide site.

Newsgator

Newsgator provides a suite of social features that run on top of Microsoft SharePoint, including Q&A, microblogging and idea management.

Pulse

Pulse is an enterprise microblogging platform from Neudesic. In addition to its core microblogging functionality, it features a Q&A section called Connect with Experts. Its Q&A capabilities are very similar to Quora's. For example, users can vote answers up and down, or can ask questions of a specific individual. Like Newsgator, it can run as an add-on to SharePoint.

Socialcast

Socialcast started life as an enterprise microblogging tool, and added a Q&A feature earlier this year. Socialcast is, along with Qontext and SimplyBox, one a growing number of enterprise collaboration tools that can be embedded in existing applications. This means users can access activity streams, status updates and questions from the applications they already use every day. CEO Tim Young believes this will be the key to success for its Q&A feature. If users can both ask and answer questions from their standard applications, the tool has a better chance of being adopted and providing value. This helps solve part of the problem Opzi sees in terms of ingrained habits.

As for routing, Socialcast monitors your behavior when using the system to determine what your interests are -accounting or Ruby, for example. When someone asks a question that's related to your interests, you'll be notified. It also has topic sections that users can check manually or subscribe to.

Yammer

When Yammer launched its new social platform last year, expanding beyond its microblogging roots, it added a Questions app that gives users basic Q&A functionality.