There's another element of hashtags which is extremely important to companies and organizations (or even committed individuals) interested in listening to their ecosystems. It's called semantic analysis—the reading of conversations for meaning.
At Causeit, we often use outlines or other organizing tools to help process the huge volume of information and brainstormed ideas in staff or client meetings.
We've struggled to find a solution that works to meet the needs of our clients across the board, though. Simple solutions like word processing documents are often too limited, graceful desktop apps cost money and/or are platform-specific and may not share easily, and web apps online only work with a good internet connection and often have limited features.
In a blog entry from GTD Times we may have found a solution in Comapping. It's not 'battle-tested' yet, but seems to be an affordable software-as-a-service (SaaS) solution for sharing thoughts, collaboratively authoring outlines and mindmaps, and even beginning the work of coming up with task delegation. It looks like it will work both online and offline (using Adobe Air), and the interface, while not the sexiest, is a good blend of power and entry-level accessibility.
Jury's still out, but you can check it out at Comapping.com.