I imagine in the future as the internet improves and compression algorithms improve, games will be streamed. This would probably be cheaper for the consumer since hardware follows economy of scale for the game companies. Also, you won't be required to run any special software on people's computers. Porting to new platforms is trivial, game consoles become super cheap, and everyone can play together.

The downside is you don't own the game. But this is more or less the case right now, with DRM and all. And for online games, you're already beholden to the servers.