Re: Is olive oil based margarine healthier than regular margarine or butter?

This is a complex question. Part of the issue is how modern margarines 
have been adapting to the need for non-trans fat products. They are often 
now blending different oils to accomplish what "hydrogenation" might have 
done originally.  And working with a predominantly monounsaturated oil is 
probably easier than with oils with more higher degrees of unsaturation.  
So, in the end a lot depends on what the company actually does rather 
than a generalization by ingredient.  What you would want is the fatty 
acid profile of the fat phase of the margarine -- the present of some 
monounsaturates and no trans fats would be ideal.  (And the olive oil I 
believe also adds a nice flavor and gives it a "richer" marketing image.)