Java the Language:
1. Go is more concise. You might not care, but I do.
2. Go uses explicit error return codes.
My experience is that practically and counter intuitively, explicit error return codes (that have to be explicitly checked for errors) result in more robust code than exceptions (checked or not). YMMV.
Java the Virtual Machine:
1. Go produces single file native binaries. You may not care, but if you do, that's a win.
Java the Ecosystem:
1. Go interfaces to C more easily;
2. Go has a more vibrant, more enthusiastic community right now.
3. Go advances more quickly.
(Of course, I can think of a lot more reasons that the Java ecosystem wins - but you asked to sell you on Go...)
But if you're looking for a new language, rather then Go specifically, I urge you to have a look at Nim (nee Nimrod). It's very impressive. I think it's what Go wanted to be.