QuickLook file associations

Typing $ qlmanage -m plugins will give me a list of QuickLook plugins and their associated MIME type (at least I think it's a MIME type):

plugins:
  org.openxmlformats.presentationml.slideshow -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.adobe.pdf -> /System/Library/QuickLook/PDF.qlgenerator (622.3)
  com.apple.localized-pdf-bundle -> /System/Library/QuickLook/LocPDF.qlgenerator (622.3)
  com.apple.iwork.keynote.key -> /Library/QuickLook/iWork.qlgenerator (11)
  ...
  public.script -> /Applications/Development/TextMate 2.app/Contents/Library/QuickLook/TextMateQL.qlgenerator (1.0 - loaded)public.source-code -> /Applications/Development/TextMate 2.app/Contents/Library/QuickLook/TextMateQL.qlgenerator (1.0 - loaded)
  public.plain-text -> /Applications/Development/TextMate 2.app/Contents/Library/QuickLook/TextMateQL.qlgenerator (1.0 - loaded)
  public.text -> /Applications/Development/TextMate 2.app/Contents/Library/QuickLook/TextMateQL.qlgenerator (1.0 - loaded)
  ...

Questions:

• What is the number in parentheses?
• How do I know which plugin will be used by a given file? Is it just the file's extension or is MIME type (e.g. public.plain.text) embedded in the document's metadata?
• How do I get AsciiDoc documents associated with one of the plugins that renders plain text?
• How do I change plugin associations? For example, use Sublime Text's plugin instead of Text Mate's.

The information you are looking for is contained in each Quick Look plug-in's Info.plist file. This file is embedded in the Quick Look plug-in bundle: Contents/Info.plist

The number in the parentheses is the bundle version (CFBundleShortVersionString). This should be a unique identifier for the developer to determine the exact build of the plug-in; compare this to a marketing version of 1.1.

The qlmanage manual details how to see associations and the expanded help shows more options:

qlmanage -h

For details on how to add or change associated files, see Apple's Quick Look developer documentation. The associations are set out in the Info.plist file's CFBundleDocumentTypes section.

The MultiMarkdown Quick Look plug-in provides a useful example of the Info.plist settings.