CoTweet is a comprehensive Web-based social media engagement, management and reporting solution that helps companies of all sizes engage, track and analyze conversations about their brands across the most popular and influential social communities today, Twitter and Facebook.
CoTweet is an amazing tool to focus on Twitter as an individual or business. You can view contacts and see your last interactions, make notes and assign tasks for follow up. If you need to add Facebook, it will be an expensive move compared to other similar tools that offer it for free.
Love CoTweet! I use it to manage two Twitter accounts - my personal one and the @TungleRocks account for Tungle. Makes it very easy to monitor search terms and @ messages, and to reply/post from any associated account. I've had some buggy moments with it, but I think that's on the Twitter side.
I've been using CoTweet for nearly two years, managing a variety of Twitter accounts. I like how the unified inbox brings all incoming traffic to a central location, and the ability to reply in-line. Being able to archive all those tweets is key, too.
Just signed up for CoTweet enterprise, so I'll update this as I use the enhanced features.