– Sitelinks are now full-size links with a URL and one line of snippet text.
– Links have increased from a maximum of 8 links to 12, revealing more about the websites you are searching for.
– Sitelink ranking is now also combined with regular result ranking to produce higher quality searches.
– Sitelinks also vary based on your query, where a more comprehensive keyword search will return better results.
This basically means more power to the top 1-2 results if they use sitelinks, as they grab more above-the-fold space. This will increase the need for a SEO strategy that will get your site on the top spot of the desired keywords / phrase (and of course refuel the discussion on whether this is a good move as it will be slightly harder for users to see a more diverse choice of results)