Inbox by Gmail (inbox.google.com)

This is a lot like what @paulg was talking about on his "Frighteningly Ambitious Startup Ideas" essay when he talks about replacing email: http://www.paulgraham.com/ambitious.html

And this is....what, exactly? My Gmail account already has an inbox.

Never understood this obsession with "reinventing email". Email works fine. Use filters, folders, tags and full-text search.