I've been pointed to a site that has taken substantial tracts of content from my site, then intermingled it with their own content and published it on their site. The content from my site is unchanged, -- bold is bold, italic is italic, typos replicated etc, but they've added in enough of their own material between my content -- ie., my para, their para, my para, their para etc -- that the end mix is around 50/50.
How is this viewed from a copyright perspective?