Bikeshedding: merge --show?

[Doug Philips]

All of the options so far are reasonable.
hg revert has -n/--dry-run and other unix tools (fwiw) tend to use -n/--dry-run as well.

Taking this one step further, it would seem to make sense to have this functionality (dry-run, preview, whatever) made into a global option. Doing it piecemeal seems rather haphazard. Yes, it might not have any affect on some commands, but then --noninteractive is also a global option that sometimes doesn't have any effect....

-Doug