Modern game marketing is generally 5-8 months prior to launch, and I'm not convinced they have games making it this Fall that they aren't already talking about (Uncharted and Gran Turismo), so E3 is more likely.
You'll notice that we don't actually have any Ubisoft titles outside of South Park announced either, which would suggest their three remaining titles are one November game (guessing a May unveil), and probably two E3 reveals for Q1.
Also, Sony is operating differently from the rest of the market in that they don't have much in the way of service games, so they don't have much to talk about frequently in between releases. If you look at Activision Blizzard, most of their talking is about the constant updates to their hugely successful service games.
