I\'m trying to get JavaScript to parse a date and time format for me, with the eventual aim of telling me the days passed since that date and the time right now (locally).
That's an ISO 9601 date -- they're a nice standard to work with. Try just munging it using regular expressions:
(\d{4})-(\d{2})-(\d{2})[ tT](.*)
to
\2/\3/\1 \4