"Ode on a Grecian Urn"

First of all, I have to say that this must be the most decorative urn on the planet. On a more serious note however, I find myself a little lost in what John Keats is trying to express. I get that the urn is a symbolic representation of all art forms but what more than that? In his last verse he says that "When old age shall this generation waste,/Thou shalt remain" so he seems to indicate that he believes that all art has the capacity to withstand man. However he goes on to say that the art he speaks of (of a "pastoral" nature) carries with it the message that beauty is to be found in truth---does that mean that Keats is equating Nature with Truth? Or is it more that Keats is saying that art that depicts people and man in his "natural" state is Truth and therefore beautiful?

Keats truly gives this poem the feel and structure of an ode. He praises the urn and compares it to other forms of art (poems and music to name a few), but to Keats they do not compare. There is a emphasis on quietness and silence that is interesting throughout the poem. He specifically states that "Heard melodies are sweet, but those unheard/Are sweeter;" so his focus remains on the visual aspects of the urn and the message it conveys within its silence.

The immortality of any and all art forms also gets Keats' focus within the poem. Which leads me to question why Keats would choose a Grecian Urn to make the subject of his poem. Is it another reference to the immortality and eternal lives of art seeing as how the urn in question would probably have been thousands of years old and therefore a testament to Keats' argument? Also, is there any insight to be found in his decision to choose an artform from what would be regarded as a "simpler" time? Keats does use the word "pastoral" which in terms of Shakespeare makes reference to a belief that life in the countryside was so much better than life within the court. Is there any connection between that definition and the way Keats uses it in the poem? The more I read this poem, the more questions I seem to find and the less answers I come up with.