Well, it does certainly look like there are two must-see films this summer. I have to be honest, I thought Inception was the better film purely because of its originality. That said, Toy Story 3 is hilariously brilliant and brings the Toy Story trilogy to a great conclusion. With some of the original characters missing (including Bo Peep, and the soldiers who go AWOL at the very beginning of the story), it leaves room for new characters to be developed. Including the hilarious Ken. And it allows other characters to be developed too, particularly Barbie and Buzz and Woody.
I was told it'd make me cry, but have to confess the only reason I had tears in my eyes was from laughing so much. And everyone in the cinema was laughing too.
Great Escape style action escaping from Sunnyside, one rather terrifying scene set in a rubbish dump, and a very satisfying ending, the film holds your attention throughout. My only real criticism is that it was pointless seeing it in 3D. Very little of the action came out the screen. In fact, there was more 3D from the trailers shown before than from the film itself, so to be perfectly honest, you're better off saving your money and watching it in 2D.
In short: a funny and enjoyable film.