The video game industry is so unique and compelling b/c it's the only industry where you get to see "works in progress." Why do you think other industries are so afraid to lift that veil of secrecy and show things "in process?" ruin the magic?
If producers and designers had their way, I suspect they wouldn't show off games as soon as they do. However, in the world of marketing and dollar bills, showing off games as they progress becomes necessary in order to create effective promotional campaigns. Movies traditionally have much shorter cycles than video games, and also due to to the substantially cheaper admission prices it makes it possible to promote a film much closer to its release.
Think about Too Human. It was lambasted when first revealed, but the marketing plan was to tease people to prepare for a bigger push closer to release. Games take a long time to make, so companies like to show off progress so people are aware of what teams are doing and where future dollars should be spent.
I for one would prefer to marketing start closer to release, that way a game's potential doesn't fall under the weight of its own hype.
