Mark Thoma comes down on the side of the first: summarize-and-link
One brief note. I'd just post links to stuff like most do, but if you look at outclicks, surprisingly few people click through. If it's there (and not tucked into a continuation), I think they read it (but more than 400-500 words is iffy). If they have to click through, they don't. So I try to do the summary thing even though it's more work. Only way to get some points heard I think. I think about how I read other blogs, lots of scanning, quick reading, then move on.
That's consistent with what our computer design people say - I was on the UO web page design committee - apparently getting people to click past the second level is generally fairly hard.
Me, I'm much more an extensively-quote-then-summarize-critique-and-link person myself.