Aumann agreements are pure fiction; they have no real-world applications. The main problem isn't that no one is a pure Bayesian. There are 3 bigger problems:

• The Bayesians have to divide the world up into symbols in exactly the same way. Since humans (and any intelligent entity that isn't a lookup table) compress information based on their experience, this can't be contemplated until the day when we derive more of our mind's sensory experience from others than from ourselves.
• Bayesian inference is slow; pure Bayesians would likely be outcompeted by groups that used faster, less-precise reasoning methods, which are not guaranteed to reach agreement. It is unlikely that this limitation can ever be overcome.
• In the name of efficiency, different reasoners would be highly orthogonal, having different knowledge, different knowledge compression schemes and concepts, etc.; reducing the chances of reaching agreement. (In other words: If two reasoners always agree, you can eliminate one of them.)

This would probably have to wait until May.