>> If you're doing it right, you start with a centralized service; get the product, software architecture, and data flows right while it's all in one process; and then distribute along architectural boundaries when you need to scale.

I'll add one more modification if you're like me (and apparently many others): go too far with your distribution and pull it back to a sane (i.e. small handful) number of distributed services, hopefully before you get too far down the implementation...