E3 serves two important roles in the game calendar. Firstly, of course, it's a product showcase - the one week in which all of the world's specialist games media is in one location, and the ideal timescale for product announcements for the year's Christmas sales period. E3 has, as a result, traditionally been the springboard for major launches, both hardware and software, with even formerly reticent Japanese firms gradually coming around to the idea of focusing their announcements on the show.
The second role, more of an emergent one, is E3's position as a windsock for the industry's trends and directions. Put so many product announcements together in one place, and you provide a wealth of data for pundits to work from. Couch them in large, glitzy press conferences, broadcast all around the world on the Internet, and you create a clear, visible and very public indicator of where the industry is going.
So on that front, what do we learn from this week's show?
One could argue that we see that the casual market, as pioneered by Nintendo in recent years, is now firmly entrenched at the heart of the industry - but this is nothing new. The focus granted to PlayStation's Move and Xbox' Kinect in their respective conferences is mere confirmation of a direction which was already well-understood.
For all the technical innovation and clever hardware on display, both products are simply chasing Nintendo's coat-tails at the moment - not the position Microsoft and Sony had hoped to be in at this point in the generation, but equally, nothing new to those who have been watching this saga unfold.
What was more interesting, in my view, was watching all three platform holders struggle with one of the most important concepts introduced by this casual revolution. Casual gaming cannot be seen simply as an end, but also as a means - a means to introduce a whole new audience to the wider world of interactive entertainment.
Casual games should encourage people to pick up the controller (or not, in the case of Kinect), and then, having demystified the world of gaming, beckon them onwards to explore further. If millions of people are playing Singstar, Wii Fit, or Dance Central, and none of them are moving further upstream to explore other games, then the industry has fallen flat on its face in one of its greatest challenges.
Only Nintendo gave this concept a name - "bridge games" - but then went on to demonstrate that the company isn't quite au fait with the idea just yet, by showing off Wii Party, a title placed firmly and resolutely in the casual ghetto.
I shouldn't be too snide; Nintendo is by far the most successful of the platform holders at creating true bridge games. The real irony was that it was mislabelling Wii Party as a bridge title only moments after a demonstration of one of the finest bridge titles imaginable, the new Legend of Zelda game, which adapts widely understood and liked Wii Sports Resort control schemes into a fun, accessible game world. Like Mario Galaxy and Mario Kart before it, it has huge potential to push legions of casual gamers upstream and encourage them to engage more deeply with games.