In theaters June 18, 2010.

High-definition Quicktime links after the break:

High-def links:
http://movies.apple.com/movies/disney/toystory3/toystory3-tlr1_480p.mov
http://movies.apple.com/movies/disney/toystory3/toystory3-tlr1_720p.mov
http://movies.apple.com/movies/disney/toystory3/toystory3-tlr1_1080p.mov

Same trailer, different sources: