Sony doesn't appear to really need a great E3 for all the reasons said by others.
Nintendo does need a great E3, if only because they have told their investors they want to ship 20m units this fiscal year, so they have put pressure on themselves to deliver a huge year.
From a gaming perspective, MS does need a great E3, for the reasons said above. On another level, Xbox is a very small portion of Microsoft's overall business, so I doubt Satya Nadella (MS's CEO), is all that concerned about E3.