Hoople - 8:48 pm on Dec 18, 2012 (gmt 0)
All good examples (above).
I use 12-NOV-2012 and 21-NOV-2012 to cover those cases, myself and international use of the resulting file(s).
The advantage in my thought (quoted above) in the creation of the above was: no one needs to figure out where I'm from to then interpret that date.
Said differently I don't have to say 'to those not in the USA this date isn't in your preferred ordering' ever :-)