Most Tweeps (twitter users) already know this tool/site, but I thought I would comment on it for those who don't.
Summize is a great search tool for tracking conversations that are taking place on twitter. On the home page, it lists the most searched topics and lets you view the conversations taking place. This can be an incredibly valuable tool for marketers looking to engage in dialogue with the consumer.
Recently it is purchased by Google, so I'm assuming that can only help with accurate search results.
Check it out.
Hopefully, AT&T is paying attention to some of the conversation going on.