Also been on Tribe since the summer (thanks @8artd for the heads up). At first I thought "really, another messaging app?" (Not trying to be a hater) But then I tried it out and it really is different. It's hard to put your finger on it but once you try the experience - you'll see. The design, the experience, the "fun."
I also think @cyrilpaglino is a huge part of the X factor. He's continued to impress me with his product vision, design acumen, and true hustle (not to overuse the buzzwords). He picked up from Paris, got a hacker house in SF, and has a wall full of post-it's for the roadmap. (@jtriest can testify)
Can't wait to see what this team builds next - "see" you all on Tribe!