I'm not sure why so many folks are worried about this game coming out. ICO was originally announced as a PS1 game, then it disappeared for for a while only to be reintroduced as a PS2 game. Granted, the timeline was significantly shorter for development, but the scope of the project was significantly smaller in scale.
Every time one of the [now former] developers has mentioned the game, they've said that it's still being developed. Every time. No matter how short their explanation is, this should not be a cause for concern.
When Sony finally unveils The Last Guardian, it can be done very dramatically. "After 7 years in exile..."
I can't imagine Sony using so many resources for so long, only to not want anything to show for it. Especially when there is a consistent amount of hype from their fan base that will likely never go away.
I'll continue to look forward to The Last Guardian, and will no doubt purchase a PS4 specifically for it one day.