I think, and this is just me giving my opinion, (not meant to bash anyone at all, it's actually more of a heads up I guess), the issue with most of the logos posted is that they don't really refer to Minecraft.
I'll just set an example.
This one. I understand that it is related to the 'beast' and all, but does it really call to the game at all? If you put just one of these logos in front of someone who doesn't know at first about this project, I suppose they'll first think it's a Skyrim Modpack, probably.
I think you guys should focus more on trying to make it, as the brief says, recognisable to Minecraft fans. It's a game about cubes. Use cubes! (or not!) No round edges, make it rough. Focus on the people you're trying to reach. It's really nice to make awesome stuff full of cool looking effects, but you gotta keep it close and related to the product at hand and what you want people to see.
Well, that was me trying to help.