I think paying by mining is a good thing and I'm surprised how unpopular this view is. I don't particularly like ads and making a small payment or subscribing is a way too much hassle for a quick visit on a news site. I'd be totally ok with the site consuming up to 90% of my cpu while reading an article.
It's great to hear that Mozilla continues to improve Firefox. I can only hope that they manage to avert a full Chrome-is-the-new-IE scenario, it's already pretty bad (can't even file taxes in FF only Chrome)