I would like to see a preference so I can render markdown (I use Multimarkdown mostly) in a user selectable app. I use Marked.
I'm using Marked, too. You can simply drag the file icon from the window title in Textastic onto the Marked icon. It works excellent.
I use Marked even with Multimarkdown Composer (I'm working with beta 2 version right now). Like reading Brett's blog but find myself tying out too many markdown apps ;-). IMHO for iPhone - Textastic and Byword are the best, for Mac combination of Marked with Byword and/or Multimarkdown Composer and now Textastic. Byword is good until the file gets long and without navigation to #...# headers it becomes painful but it sync's very nicely using iCloud (or Dropbox).
Yes, dragging the icon works even for files that are saved to iCloud.
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