Somewhere there's always a natural limit, be it because of impossibility to reach higher speeds without heating the PC too much up or because of HD's need to grow larger for even more space. Eventhough modern games can be today up to 4GB large it takes more and more time to produce them. And the bugs in the games grow, together with growing absence of fun factor in them because of the work of a 100men+ team which suffocates the imagination and creativity.
I doubt there will be games much larger than 10GB in near future, unless there will be only very few games released on costs of increased size, better (how much better can they be yet? :eeeeeh
graphics and longer play-time. Unless the tendence will go entirely over to games that are like MMORPG's that are updated, improved and corrected constantly all the time, and who knows, maybe in 3 years it will be a completely normal and daily thing to pay monthly for play a game. And then there slowly will appear flat-rates for a bundle of many games together, similar to the flat-rate of DSL providers today... :whistle: