After just a week’s experience with Twitter, I can see a real need for a spam filtering mechanism (like Akismet for WordPress). The ratio of spam to good tweets is already bad, and getting worse everyday — and that’s after just a brief experience with the service.
If not addressed soon, this could be the Achilles’ heel for mainstream adoption of Twitter as a highly valued communications platform.
In the meantime most of my friends don’t use Twitter today, so it has minimal value to me on a personal basis… It’s like the early fax machine market: you can have the best fax machine in the world, but if the people and companies you most want to reach don’t yet have fax machines themselves, you can’t communicate.
Network effects, in other words, as applied to each person’s own network. You need a critical mass within your own network to realize the benefits.