Yeah, semi-old news. I'd be interested to hear what they do with the new guy. Opeth is basically Mikael Akerfeldt anyway. It'll be neat to hear what this new guy brings to the table.
Well, Fredrik only toured with Arch Enemy for a few months when Chris Amott left the band. He never wrote any songs or anything. He was more of a fill in than a true member of the band. He's been in some other bands, but I've never heard any of them.