My second reaction to GroupTweet was: Ok, this could be useful for communicating with a subgroup of your friends. As people use Twitter, they tend to accumulate followers that are spread out geographically. If you’re wanting to make plans to go out on Saturday night, those tweets don’t necessarily need to go to people that live hundreds or thousands of miles away from you.
My third reaction to GroupTweet is to unfollow those I’ve followed, and not join any others. The problem with GroupTweet is it undermines one of the biggest strengths of Twitter: the ability to control the experience. When you follow someone else’s group, you allow that person to decide, at least partly, what you receive. The group owner chooses who to allow in the group, and when they let someone in, you start receiving their tweets to the group, whether you want them or not.
Just to be clear, I haven’t had an actual problem with GroupTweet yet, like getting spammed or anything. It was just seeing a tweet from someone I hadn’t followed that made me realized the idea has a fundamental flaw.
So I could see starting my own group, but I can’t see joining someone else’s without a clear set of rules on who will or won’t be allowed to join — much like the example GroupTweet gives on their home page. I don’t know that there’s a real solution to the problem without making the GroupTweet service significantly more complex. It may be that this is an idea with limited application until Twitter offers more fine-grained control of what you receive.