Just as a comment, I see plenty of uses of title case within the menus
at BBC.co.uk.
While many of the headlines don't use it, many titles in menus including
ones that very certainly aren't simply proper nouns seem to use title case.
Instead of arguing based on how often people see it used or don't is
there some actual reference we can resort to as to when title case is
appropriate in UK English? Judging from the BBC website, the Telegraph
website and Amazon the big difference between US and UK use of title
case is simply that they use it less (or perhaps, more inconsistently)
as many lines seem to use it partially ("Terms and Conditions of
reading") where title case seems simply to be used to emphasize certain
words rather than following any sort of rule.
Judging from these websites, it looks to me as if it's not as uncommon
in UK English as some in this thread seem to suggest.
