Given the new trailer shown at GDC, I have a feeling another trailer will probably not happen unless the game is to be delayed until 2012. I really believe the game will release in November of this year (unless it's to be held back to share a release with a new console a la TP), so I think it might be mentioned in passing that "it's available for play on the show floor, and the release date will be ____."
I base this quick discussion of it on the fact that the opening of last year's E3 was dedicated to the game. The focus will most likely be about the performance of the 3DS, and what games will be coming for that system. I would almost think the Zelda focus would be more about OoT3D if it hasn't released in the first week of June (ie - a release date, because when they are close to E3, they like to excite people by saying "It's out next week!") and the 25th Anniversary Zelda surprise. SS' info will be a brief mention in this Zelda window.
I feel the demo will be the same one they have brought around since last E3 as well. They tend to make one demo build of a title and leave it at that. It would surprise me if they made another one showcasing what they usually do for Zelda - a field area, a dungeon, and a boss battle. If they are to update a demo, then again, it will be ecause the game's in 2012 now.
Nintendo usually provides new content to please people when a game's delayed. Otherwise they rely on the content they've already made public up until the month before the game's release. (Most recently, Metroid Other M and Donkey Kong Country Returns shared this pattern). Because of this, I almost hope there is NO new SS info other than a release date!
