One of the problems most online games (Pokers, MMORPGs, etc) have is cheating. Some ways of cheating are easier to detect than others (like alteration of the player's coordinates, etc) however, other like Bots or macros that harvest and increase the players skills etc are harder to detect specially for humans.
You could make some sort of AI cheat detection system (platform) that could spot these behaviors and flag them as suspicious for a human to review, like casinos do.
Emphasis on:
- Integration to existing different game styles/platforms (FPS, Car Games, Turns Based, MMORPGs, etc).
- Extensibility.
- Performance (False positives, bottlenecks, responsiveness, etc)
I'm thinking of dynamic/static data analysis through expert systems of some sort.
Another interesting approach would be to device a server architecture for realtime games featuring:
- Decentralized distribution of servers (p2p)
- Load balancing.
- Non partitioned virtual world. By this i mean, if Alice is playing in server A and Bob is playing in server B Alice and Bob can see each other and interact without the need of changing servers) A derivative of this topic would be the synchronization of the virtual world state (Alice on server A affects the virtual world in some way ie. builds a house, kills the main character on some unique quest, etc, then Bob playing on server B can see the house, or is no longer able to take the quest or the quest is canceled if already accepted)
I hope this helps, ill see if i can come up with anything else.