Oh, and another btw here...yeah, this "War Horse" movie has the look of a winner, if ya ask me, though its plot sounds an awful lot like an old 1946 film titled, "Courage of Lassie", starring a young Liz Taylor. That one actually is pretty good, as it too is about a Service Animal, but it's set during WWII, not WWI.
It's shown on TCM from time to time.
(...btw, don't let the title confuse ya...the collie in this one is actually named "Bill" and not "Lassie"...word was the producers of it wanted to cash in the popularity of the first Lassie film)