If the web properties could successfully argue that their copyright extends to how the content is displayed, I think it is likely they could get a lot more bang for their buck by suing Microsoft for the mangled content that comes out of the many millions of IE 6 browsers still being used out there. :)

That said, I highly doubt either lawsuit has much of a leg to stand on. Content transformation is a long standing and tacitly accepted feature of web protocols. Caching, zooming, and even assistant technologies such as a screen or braille reader would run afoul this argument.