Now that have [code highlighting enabled][1], we need to determine how 'automatic' it should be.

The code highlighting engine works in two ways:

 1. Automatic inference of the language in use via the tags on the question, and
 2. Manual specification of the language in a code block, overriding any language behavior on a question tag

Currently, we have highlighting enabled for a [large number of tags][2], a default set from Stack Overflow or some such.  We've already disabled automatic highlighting on a small handful ([tag:ios], [tag:iphone], [tag:php]) due to awkward highlighting on questions, but we need to decide what approach to take for a consistent behavior across all tags.

  [1]: https://meta.serverfault.com/questions/2717/vote-do-we-want-code-highlighting
  [2]: https://meta.serverfault.com/a/2718/72586