At any rate, the only thing the new intermediate page does for me is introduce another mouse click, thereby hampering flow rather than enhancing it. I'd be interested to learn what problem or feature request the current solution addresses.
So: -1. Which isn't to say I don't appreciate the concept and effort. :)
Counter-proposal, for when I hit "Mark All Forums Read":
\nfor forum in fora:\n if forum.datemarked <= now:\n forum.datemarked = now\n
...that way, if I've marked a forum for 2030 (forum.datemarked = date(2030, 1, 1)), it won't be modified by "Mark All".