Is Twitter the media?

Last night while attending a lecture on developing a multilingual web strategy for your website, I posted this to Twitter:

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A blogger who goes by the name of Hillarygayle challenged my position, saying that she couldn’t understand how a medium like Twitter could jump the shark. “Content can,” she wrote, “but users give Twitter its content & whatever we say goes.”
While I understand her point, I don’t necessarily agree. The difference seems to be that she thinks of Twitter as a medium, like television, while I think of Twitter as a product, or in some ways, a destination.
If you were to consider it from her point of view, broadcast media does not fall out of favor, it simply changes based on the market that drives it. She used television as an example: television hasn’t gone away, it has simply diversified to include different methods of broadcasting (free television, cable TV, digital, and satellite, for example).
To my mind, Twitter is a product, like a magazine, CD, band, or novel. These things are commodities, and like any commodity that is bought, sold, and traded, the product can reach a point of supersaturation in the market. People do grow bored with a product and toss it aside. Think of indie bands who were popular when they were housed on smaller labels, but as soon as they gained mainstream success, many longtime fans abandoned them as more “middle of the road” types discovered their music. Magazines launch and fail all the time, television shows are canceled, and CDs end up in the remainder bin.
As Twitter’s adoption rate continues to grow, will it end up in a digital remainder bin? Can a service jump the shark, as awareness trickles down to the general population? Is Twitter a medium, or a product? Is it both or neither?
Discuss in the comments.
*Image by RichieC via Flickr