I've noticed that, through the years, company press conferences harness a certain "personality" once they've gone through the motions over and over again. Nintendo, for instance, bleeds this "ultra-cool older brother" attitude on stage. This is mainly a product of the writers', I think. Microsoft on the other hand emits a certain pride in their announcements, something we're bound to see in spades come tomorrow. Sony continually takes on a more reserved, near-humble persona. More specifically, you may notice that they make frequent nods to their audience -- they're well-aware of who's sitting in the seats, which lends them an understanding of their fans.
These attitudes are achieved in various ways -- as mentioned above, their writers; the presentation of the...presentation; or even the presentees themselves. Whichever device these companies yield, I want to know: