Dave Winer posted a few days ago that he was looking for examples of OPML in “production”. I assume that means “being used by someone or in an app”. I thought I would contribute a few items…
Zylstra.org – Ton Zijlstra’s OPML blog roll in a human readable form (reference)
Zylstra.org – Ton Zijlstra’s booklist in OPML (reference)
AndySylvester.com – Andy’s beginning booklist in OPML (reference)
AndySylvester.com – Reading lists in OPML for the River5 feed reader/aggregator