I've seen some suggestions that because it is a devolved matter and partially embeddd in the Scotland Act it may not be straight-forward to repeal it, that the Supreme Court (in the person of the retiring Lord Gill is begining to suggest that some UK legislation is a special more enduring class than other legislation) and that it open to the Scottish and Welsh Parliaments to re-enact the ECHR.

(Here from a link from Andrew Ducker on LJ)