I own the core set and most of the expansions and I am really curious what changes/tweaks they added to the Player's/GM's guide. I understand they are fairly minor so I don't want to buy another book at this point but I still want to know.

i.e.

I know there is a change to the Spear to make it Unreliable 2.
I also think they clarified it so that 2 Boons can be used to add 1 to initiative (or something like that).

What other tweaks/changes?

I also know they gave some additional examples/uses for banes/boons and any help there would be nice as well. Hopefully they sell a pdf or add these to the errata.

It depends somewhat on how your interpreted the Core Set ...

But I'll mention that talents used on party sheets loose a recharge token at the end of every turn now.