Sony still confirms that The Last Guardian is in development.

[Rafie]

Darwinianevolution said:

Why would the game being mediocre cause a migration of fans from Sony to others? Neither Ico or SOTC managet to reach even two million units sold (not even the PS3 combined edition), this games are really niche.

For the simple fact that this game has been hyped more than any game in recent history that's been announced. Yet we have nothing on it, but a "we're still working on it" quote.  If the game is better than medicore for all of the development time it spent, then rest assured we will be seeing some fans migratiing.

Sales have nothing to do with what I'm stating here. Also SOTC and Ico were in a different market back then. The market has changed since then. Still you're correct that it's a niche title. Just saying here that Sony will lose trust of the fans that have been waiting on this game for years if it's not phenomenal!