I think that you picked a rare counterexample to the normal behavior of bloggers. Gruber does not write like most bloggers; he does an excellent job of finding interesting articles and piquing interest in them without using a large amount of their content. When his posts are long, you can bet that they are full of original ideas and material.

In the Gawker example, the blog post is eight paragraphs long, four of which are lifted directly from the source and the rest summarized from the most interesting parts of the source.

I think that if everyone blogged like Gruber did, we wouldn't be having this discussion at all.