Moderator Notice
This is not the place to debate the merits/evils of bitcoin mining in general. Kovid has made it clear that it will be opt-in only, and that no mining software will be installed on a user's machine until such time as they explicitly opt-in to that donation method.
Everyone can do their own research, and make up their own minds about the (de)merits of bitcoin mining in general.
So let's please return to indicating whether or not you would be willing to donate to calibre via the opt-in (and add-on) method Kovid indicated it would be.