I believe definitions is what is going on with this post by "Kressilac" (Derek Licciardi?):
http://blogs.elysianonline.com/blogs/derek/archive/2009/05/29/6400.aspx I'd guess we do hold the same values.
Derek argues that portions of an MMO server are suited to using and best implemented using web technology. I absolutely agree. I call these parts of the system "Game Services". Most would be accessed directly from the client. Examples:
- profanity filtering,
- shard status, open, full, down, locked, capped
- in game search/player online,
- clan/guild management,
- item trade,
- match making/lobby,
- persistent messages/email,
- reputation management/community services,
- in-game advertising
- CSR account locking
- patching, streaming patching
- custom content
- character annotation, friend lists,
- knowledge base
- voice chat
- Maybe: inventory, quests, crafting (touches in-game entities)
Most of these systems are "decorative" and are for the community aspects of the game.
The complication arises where the data managed by these services is affected by or used by the simulator (I.e. in-game logic). E.g. the number of members of your clan changes Mana recharge rate. I'd suggest that most of those kind of communications are not critical to be transactional or latency critical or can have the game design bent to accommodate that restriction.
There are a couple of those game services (especially those interacting with items) that are entangled. The easiest way to deal with those is to transfer ownership of the Entities in question to one system or the other such that there is no synchronization needed other than at the transfer. I'm betting that is how WoW does auctions and mailing of items.
My "run screaming; it sucks" article is my thinking about the core gameplay/simulator manipulated Entities. What Derek calls Real Time Data. To me that is the "hard problem". All the rest of the stuff can be handled by web-tech, and that is a solved problem (waves hand dismissively), and not so interesting.
Well. There are a few interesting issues, like coordinating authentication. But the coolest payoff (as Derek states) is that these things automatically become available offline via browsers, mobile devices, etc.
BTW, I'm working on another contentious article that more fully details the issues that drive my opinion about DB-centric game state management.