Caitie McCaffrey, distributed systems engineer at Twitter, talked about the benefits of stateful services which are less known than their stateless counterparts in the industry and how they can be scaled at the Strange Loop conference. The benefits include data locality and higher availability and stronger consistency models. McCaffrey also gave real world examples of stateful services.
Causal Consistency models offer an alternative Eventual Consistency for distributed systems; both models should be weighed against your system's requirements and risk tolerance.
The recent theft from several BitCoin operators has sparked a debate whether eventually consistent databases are useful or not for banking.