In the search community, it's widely known that each of the major search engines often experiment with their algorithms, chopping and changing factors which they feel might enhance their search listings. Most of these tweaks are made behind the scenes, and very rarely does Google, Microsoft or Yahoo come out and openly broadcast what they've changed and instruct SEOs as to how they might cater to the new changes.
It is a little frustrating that we have to wait for most of the algorithmic changes to be employed here in the UK, but we've already spoken about that, so we'll move swiftly on!
The change itself, is clear to see if you go to google.com and search 'exhibitions at amnh' ('AMNH' being the American Museum of Natural History). Google has developed an understanding of context here (and in similarly structured search criteria), and believes that those searching for such results are likely to benefit from more results from the AMNH website.
Before the algorithmic change, the AMNH website would have been assigned two SERP positions on the first page, but now, as you'll see from the image above, the site occupies the first seven results.
Whilst I think the development is probably a good one, in my opinion, there's still some work to be done. It feels wrong that the same site occupies so many results without giving the user much of an indication that the results reference the same site. Yeh, I know the web address is shown as part of each result, but that involves users having to manually look through the listings and visually compare the web addresses. In other search results where pages on the same site appear consecutively, Google insets the second result (and the third and fourth and so on...) to let the user know that both results relate to the same website (see image below).
I think that this type of result operates far better than the new results do. You don't even have to look/compare the web addresses - the inset results immediately communicate that they all relate to the same website.
I'm probably being a bit picky about this, but I should imagine that there's nothing more irritating than searching something only to find that each result you click on is for the same, unhelpful site. If the results were inset, and you didn't like the look of the first one you clicked on, you could bypass the rest quite easily. I suppose we'll just have to wait and see if Google changes it's new feature, and it'll be particularly interesting to see whether they change it before it gets rolled out on google.co.uk!