I should also point out that "attaching an uneditable review" is doable right now--all one has to do is put an external link on the talk page.
I like the uneditable review idea; it's simple enough so that it could actually work. I wouldn't put the links on talk though: nobody reads old talk pages, and the reviews wouldn't be firmly associated with individual versions of an article.
A review of an article version should show up as a link on the History page, next to the reviewed version. That link could point either to a wiki page only editable by the reviewer, or to an external web page, whatever the reviewer prefers. It would also have a link to the reviewer's user page, where they could convince us of their brilliance, and where one would hopefully also find an automatic "this person's reviews" link. Reviewer status should probably be by invitation only.
With a bit of luck, some of these reviewers might end up as Wikipedians in this evil scheme.
Axel