Actually, an incorporeal touch attack is a specific thing. See for instance the monster entries... they list "incorporeal touch," which the incorporeality entry explains as ignoring armor and shield bonuses except for those provided by force attacks.
For example, a ghost wizard would make an incorporeal touch attack to deliver a draining touch, but a regular touch attack to deliver a shocking grasp spell. The latter would ignore mage armor and bracers or armor, while the former would not.
However, as far as I know the armor bonus from bracers of armor functions exactly like that of armor with the ghost touch property, for touch attacks, incorporeal touch attacks, or anything else. The only difference is that the bracers cannot be worn by an incorporeal creature.
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As for a cloak of mage armor, I'd be OK with a 2000 gp item that lets you cast the spell 5 times per day at CL 1. The benefit of continuous use clearly has to follow the example of the bracers... maybe a small discount for lowering the caster level, but nothing much.