We watched Toy Story 3 last night. Tom Hanks got his break in Splash out of hundreds who read for the part. As in Blink this was a first impression decision by the producer Brian Grazer. It was because Hanks was instantly likable. He wasn't the funniest or the best looking actor interviewed, but he was able to do 'mean' and you forgave him, even if he made choices you disagreed with, he was still likable. None of us knows him, but we get the impression that he is decent, trustworthy, down to earth and funny. He was made for Woody. Or vice versa.
That being said I didn't think it was as good as Toy Story 2, though probably deserved its Oscar as there was nothing better on show. I think that should preclude a Toy Story 4.