The official position of the graphic design industry in general, including AIGA of the USA, GDC of Canada, and ICOGRADA (international), is that performing speculative design work is unethical and hurts both the client and the designer. In a nutshell, any type of graphic design work which is done with possibility of no payment (not counting pro bono) is spec work.

Want to know more? Here's some good resources:
ICOGRADA's guidelines for soliciting work from professional communications designers (pdf)
Graphic Designers of Canada - About Contests and Speculative Work
AIGA - Position on spec work
The No!SPEC Campaign - an online resource and petition
Articles by:
Jeffrey Zeldman
David Airey
Habib Bajrami

The other day I had the pleasure of giving a reference for a friend of mine who was applying to be a missionary with MCC. The charity provided a form for me to fill out and I had to rate him on a number of characteristics. For the most part, it covered general qualities such as "Christian Faith and Commitment", “Creativity”, and “Leadership Skills”. Although I attend a Mennonite Brethren church I was a bit surprised at the priority they put on “commitment to peacemaking and non-violence”. There were no other doctrine-related topics they were concerned about, and that concerned me. It also got me thinking about my own commitment to peace, and the next morning the verse below came to me.

When “Peace!”, like a mantra, attendeth my lips,
Where death camps and genocide go,
When evil runs rampant and I fight it not,
It's not well in the depths of my soul.

I am normally against making parodies of worship hymns. I'm also normally against violence. However, I believe in certain circumstances there is a greater end that must be achieved, and it might mean that you need to endure the ugliness of war, or write lines of doggerel to make a point.

I believe MCC does a lot of good godly work. I just think they need to rethink their priorities. There are doctrines that should be deal-breakers when hiring Christian workers, and I don't think pacifism is one of them.