The trouble is, no walled garden will be able to replace email. Email works because it's open -- anyone who can set up an MX record and an SMTP server can send

The trouble is, no walled garden will be able to replace email. Email works because it's open -- anyone who can set up an MX record and an SMTP server can send and receive email. Social networks will succeed if someone can figure out how to make it open in the same way. I'd say that's probably the future of communication on the web... some amalgamation of email, IM, and social networks. Meebo gets close, but I think for IM to work, it has to be integrated with the desktop. Maybe an AIR version or something like that...?