OK, I never really left Gmail, I just check my Gmail through Mac mail, but Google Buzz might make me reconsider using Gmail exclusively.

This from the official Google Blog via MLM Blog:

We’ve blogged before about our thoughts on the social web, steps we’ve taken to add social features to our products, and efforts like OpenSocial that propose common tools for building social apps. With more and more communication happening online, the social web has exploded as the primary way to share interesting stuff, tell the world what you’re up to in real-time and stay more connected to more people. In today’s world of status messages, tweets and update streams, it’s increasingly tough to sort through it all, much less engage in meaningful conversations.

Our belief is that organizing the social information on the web — finding relevance in the noise — has become a large-scale challenge, one that Google’s experience in organizing information can help solve. We’ve recently launched innovations like real-time search and Social Search, and today we’re taking another big step with the introduction of a new product, Google Buzz.