A short time after the fires in SoCal hit the news I noticed quite a bit of traffic coming from Google's main search page. At that time, a search for 'Santiago Fire' incorporated blog posts at the bottom of the page and one of the 3 highlighted posts was mine. The inclusion of blog posts is part of Google's 'universal search' paradigm in which, for any search, a mixture of different types or results is presented interlaced in the standard one dimensional result page.
One of the maxims of interface design is predictability. An interface shouldn't change from under you. A search now for 'Santiago Fire' doesn't produce blog results. A search for 'Gordon Brown' produces, at the top of the list, first images of the man himself, then news articles then organic results. Actually - it does if I do the search on IE6, but not if I do the search on Firefox (Japanese).
Is there anyway you can predict what you will get? With some luck and some guess work, one can look at Google news and produce search results that will contain blog posts. A search (right now) for Robert Goulet - the Camelot star who died yesterday, produces links to these three blog posts (note that the last, a post on TMZ, results in a redirect to the main page, perhaps they removed the post - oops!). A search for 'Google Phone' also very visible on the Google news pages, doesn't produce any blogs. Note also that the blog posts that are highlighted on the search page are not the top most relevant posts (according to Google's blog search engine).Two of the Robert Goulet posts are on the first page of relevant blog posts, but not the third.
In addition to the lack of predictability in the results page, one can't page through the mixed results. The first page offers the interlaced results, but going to the next page only offers organic results.
I think it is great that Google is addressing the interface problem - the web is so much more than a bland list of pages. However, the current approach seems more confusing than, say, Ask's 3D layout (though I notice that that is shifting over time too...)