Artoomis said:
Feel free to edit it to make it more neutral.
Well, here's a revised version of the summary I came up with before. I believe this covers all standpoints people have stated in the past couple of threads (in no particular order). Points can be mixed and matched freely:
1. Monks can take INA. Their unarmed strike counts as a natural weapons for spells and effects, and feats are effects.
2. Monks cannot take INA. Their unarmed strike counts as a natural weapons for spells and effects, and feats are not effects. (Many secondary sources are incorrect per the Primary Source rule.)
3. Monks cannot take INA. Their unarmed strike counts as a natural weapons for spells and effects. Feats are effects, but their prerequisites are not. (Many secondary sources are incorrect per the Primary Source rule.)
4. Monks can take INA. The primary source is ambiguous, and other sources clarify that they can.
5. Monks can take INA. The monk is underpowered, and this feat helps balance them.
6. Monks cannot take INA. INA is too powerful of a feat.
7. Monks cannot take INA. INA was intended for monsters only. (Many secondary sources were written by authors that did not follow the original intent.)
8. Monks can take INA. INA was intended to improve attacks without weapons.
9. Monks can take INA. INA was originally intended only for monsters, but WotC has changed their minds and ruled that it is OK for monks.
10. Monks can take INA. Unarmed strikes are actually natural weapons.
11. Monks can take INA. However, INA does not stack with the increased damage from the monk class, so it becomes worthless after a few levels.
Personally, I stand by #3, but also agree with #5 and #6. I really cannot see any basis for points 10 and 11, but include them here for the sake of completeness.