I agree. In particular, I wonder what, say, Metafilter would look like if every link were preceded by a diamond.

I liked it, if only because it made the text look much more uniform. I imagine it was done out of objection to the "make the link bold and blue and underlined and very different" ethos that even Google was into until recently. With this, I can just read, and if I see a diamond, I know a mouseover will reveal the anchor text and point me toward whether I want to click on the thing or not.