“I don’t want any more friends. But I do want your knowledge. That’s what’s really motivating people to use communities, “ says Tilak Mandadi, VP of Interactive and Travel Technologies for American Express.

Talik – one of the most entertaining IT execs I’ve ever heard in a long time– said seven things matter the most for effective online communities:

1. Social intelligence – learning what other people know — vs. social networking.
2. Specialized context of community
3. Exclusive content
4. Ability to transact
5. Moderate moderation
6. Participant defense of the brand (Let other AMEX customers defend the brand if someone says something negative)
7. Speed to market

The ability to transact is especially important. Tilak said customers using American Express’ “Members Know” travel community have expressed frustration at not being able to act on what they were learning about in the community, which Amex is going about changing.

Many companies are creating communities for awareness, loyalty and word of mouth, but they may be missing a big opportunity for transaction revenue — and frustrating customers in the process.