I often argue that the toughest thing about distributed systems is changing the way you think. The below is a collection of material I've found useful for motivating these changes.
Current "rocket science" in distributed systems.
One of the larger websites out there with a high write load which is not the norm (most are read dominated).
Interesting they dumped most of J2EE and use a lot of db partitioning. Check out their site upgrade tool as well.
Broad vision, way of the future type stuff.
Somewhat about the technology but more interesting is the culture and organization they've created to work with it.
Ramblings that make you think about the way you design. Not everything can be solved with big servers, databases and transactions.
Understanding this algorithm is the challenge. I would suggest reading "Paxos Made Simple" before the other papers and again afterward.