Chocolate Stout and Pumpkin Beer - Update

A few days after adding the cocoa nibs to the chocolate stout I checked in on it to find a gnarly surprise.  It looked as is a lacto bacteria infection had taken place as a huge pellicle laid across the top of the beer.  I opened the mixed batch of chocolate and pumpkin and the same thing.

I got pretty upset and decided to just pitch the chocolate.  As I was pitching the beer down the drain I put my finger under the stream of beer and took a sample.  It tasted great. 

Realizing I may have been throwing away good beer (less than a gallon) I decided to research cocoa nibs some.  I read on another blog that someone had the same experience.  The responses on sites like Homebrewtalk.com suggest one of two things may have happened:

1. The fatty acids and the oil from the cocoa nibs are leeching out into the beer and interacting making a pellicle looking mess.
2. There is a bacteria on the cocoa nibs that should of been sterilized by placing the nibs in some vodka prior to pitching them.

With this in mind I decided to  save the mixed batch of pumpkin and chocolate stout to see what happens. I will be bottling this week if I feel it was OK.  Maybe a sour chocolate pumpkin stout?