Community Manager - marketer, product person, support? And where does Social Networking fit in the mix?

I'm frequently involved in debates about the skillset that best embodies a successful online community manager.

How do you define their responsibility and what experiences are most valuable therein?

At what point to you believe the role of a community manager crosses the boundary of the on-site community and steps into the role of SEO, social networker, and evangelist?

In response to Matt's answer:

I suppose what I'm trying to work out is that while a community serves many purposes; it should strive to accomplish 3 (primarily):
1. Acquire new customers/users
2. Support and retain existing users
3. Extend a brand beyond the realms of its product/service and beyond the confines of its domain

I think too many communities are simply message boards/forums put up by companies who want to play a role in the social evolution of the web. To make the communities appear innovative they incorporate twitter (or perhaps as much as a page of tweets).

So, what skill set can help evolve that half-baked community into a thriving discussion related to your business and a social environment in which users and employees can connect?

Don't take this the wrong way because I agree with your assessment but I believe that defines the person capable of supporting that simple community in which someone needs to engage and respond. What about extending that community into other networks, creating viral content to drive engagement, architecting (SEO) content and structure for the community that fosters participation as well as prominent placement in search.

I manage multiple communities, one that has around ~3000 members, and another that has ~200,000 members. I'd say the following skills are essential to being an effective community leader:

• Ability to articulate effectively through online mediums
• Ability to be able to respond in a timely fashion
• Ability to update and keep members in the loop and follow-up on any actions (eg. if you're having a drawing for a prize, the winner should be announced... this might be basic, but I've worked with people who don't do this)
• Personable skills
• Great in-person speaking skills if going to be at tradeshows and what not... etc.

In one word, the most important aspect is communication

That's a quick braindump. I'm sure there's more. I'd say basic SEO is useful to the company (can be taught very quickly). I'd also say the community manager is a social networker and an evangelist. If a company wants someone who is effective at what they do, I think those are all important traits to have.

Hm, I'd be curious on what your thoughts are on this subject.