jgsugden
Legend
The question comes down to this: Does the feat grant an ability that can be called spell or effect?A monk's unarmed strike is treated both as a manufactured weapon and a natural weapon for the purpose of spells and effects that enhance or improve either manufactured weapons or natural weapons
I think we can all agree that a feat is not a spell, so we can ignore that half of the equation.
Is a feat an effect? That also seems awkward. A feat is never called an effect in any WotC book, so I'm going to say no.
In the alternative, can the resulting benefit of a feat be called an effect? The answer to this question is a definite yes. The text of many feats (extra turning, for example) note that the effects from the feat stack if you take it multiple times. So, the result of a feat can be an effect.
So, the effect generated by this feat can be called an effect. It is an effect that enhances or improves natural weapons. This falls under the description of the monk ability mentioned above, so a monk, by the rules-as-written, can qualify for this feat.
As an aside: I house ruled this feat into a monstrous feat, so PC types can not qualify for it.