Microprose and Bethesda
Today I found myself working with Hasbro's Microprose division and then Bethesda later in the day. Both these appointments left me with the feeling that there's a major change on the horizon that was only hinted at in earlier games. Just about every game we've seen this E3, especially on the final day, left us with the feeling that gameplay depth is going to get much deeper in the next year. RTS games, first person shooters and even a flight sim involved RPG-like aspects.
Namely, the AI characters you're so used to working with, who are predictable and dependable in their failures and achievements, are about to receive a major overhaul. Only two games I had an extended look at didn't have skills and/or attributes as part of the feature list on their games. This seems to bode a major milestone on the horizon, where we will see games that have a more varied set of AIs working with and against you. These AI characters will behave differently and with varying degrees of success. For example, in Half-Life you could easily count on the guards who occasionally escorted you to take out head crabs better than you could since their aim was perfect.
If Half-Life was using today's technology and decided to implement this skill system, then those guards escorting you would not be so dependable. They might have a morale bar, where they'll flee after encountering a particularly nasty looking creature, or if they take too much damage. Their aim would no longer be perfect, or at least reliable, because they might have a skill of say 72/100, and in the most basic sense they could miss 28% of their shots (though, of course, it will never be that simple or easy to calculate.)
What Does This Mean?
If this skill-based AI trend continues and proliferates, it would mean that the realism of gameplay would increase exponentially. Just like difficulty in Quake 3 and Unreal Tournament is determined by AI skill not enemy numbers and the computer player's ability to cheat, RTS games could soon be like that. Not only would the general AI of the enemy be a factor in difficulty like it is now (base-building, battle control), but yours and the enemy units AI would now be different. That dragoon who always hit with its photon would have to make an accuracy check. A siege tank operator would have to make sure that he hit his target, or he might not do full damage.
To be honest, we're already seeing steps being taken to go in this direction with Blizzard's "RPS", WarCraft III and other products that follow similar themes.