When Yammer, a micro-messaging service for the enterprise, launched at TechCrunch50, the biggest complaint was that the service was one big inbox, with no way to create groups or tag messages.

That hasn’t hurt growth of the company, which had 50,000 users a week after launch. But as usage grows at a company, the “all messages” tab can get a little noisy. We are using the service religiously at TechCrunch, and the signal-to-noise ratio is getting to the point where we’d really like to move discussions to different topic areas, and follow the ones that interest each of us.

Sometime this week that will happen. Yammer will have separate groups (which optionally can be private) for various topics. And users can also add a hash tags to messages, which can be followed separately as well. The service will also allow threaded comments to segment different discussions (see image below). To see the new version and see an overview video, go here, but any actual content you create on that staging version will be discarded once it goes live.

Yammer has become an indispensable part of our workflow here at TechCrunch, filling a niche for group communication that’s better than email and instant messaging. We expect to see it continue to grow quickly.

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