"In other words, it's not close to being ready. Mosedale went on, "While we've been pretty clear for a while that calling something a beta doesn't mean that we're feature complete, what we've got now feels like it's pretty far from being representative (from a user-experience and user-visible-change point of view) of what Thunderbird 3 is going to feel like." In other words, really, really not close to being ready."
