Perusing Raptitude.com I saw this post on veganism.  Here is the comment I had on the site.

I think that the “try it out approach” is the best way to explore new options and find out what works best for you while hopefully preserving a sense of play and curiosity.
As a fitness coach I have seen great benefit whenever people choose to bring an intention to their eating.  If they keep up with awareness and experimentation they tend to keep evolving their diet and their general approach to food.  Where they “end up” isn’t really the point and neither is finding out whether the benefits are “psychological” or “physical” because both are important.
I have had good success and enjoyment with a paleo-like approach and would encourage further experimentation with it.  Specifically, experimenting with meat and dairy as separate variables.  I am very much informed by Robb Wolf and Matt Lalonde for my understanding of nutrition.  You can check out Robb’s blog at www.Robbwolf.com.
The ethical piece is tricky but it is impossible for most of us to avoid given the way most of our food is produced.  Large scale monoculture farming is also a huge problem with regard to sustainability and food quality.  The most productive techniques for food production involve a diversity of animal and plant species on the same land.
I really like Hugh Fearnley-Whittingstall’s “Meat Manifesto” on the subject of ethically eating meat.  I couldn’t find a full version of this manifesto from the River Cottage Meat Book online, most of the excerpts available seem to cut out the most interesting parts.   I really appreciate his insight about our discomfort with human-animal predation.  We generally have no problem with humans killing humans (witness the whole reaction to Bin Laden’s killing) but we are often sensitive to humans killing animals.  Fearnley-Whittingstall’s book shows a sequence of photos of one of his cows being slaughtered and it is definitely something to come to grips with and something he thinks should change our relationship with meat.
Anyway, plenty to struggle with and explore!