http://www.youtube.com/watch?v=MoZlMGU99qk
Good news? Surely it is. Bad news? Maybe as well.
So basically Unity is teasing us with this new tool and tell us to either switch tool and lost all our progress or stuck with our old system and bare with inefficiency. I'm having my programmer dilemma and go F myself x.x
Last but not least, we can still import our spine progress if new environment is supported... not sure if they will come with a 2D skeleton tool. My guess is no... and oh my, they already have something similar shown in the video.