Google are today rolling out the first major overhaul to the appearance of their search engine for a number of years. The main change is the addition of a left column, a little like that which has been used for image search for a few months, or the layout of Yahoo's Search.
It also sees some style tweaks with a richer usage of CSS and the introduction of colourful elements, more in line with the styling of some of the company's other products, such as Picasa and Chrome.
The main impact of this change on SEO seems likely to be putting advanced search and search refinement options at the fingertips of more users. This could see a rise in the number of searches by date or type of search (e.g. "More shopping sites"). The colourful icons may also attract more users who are not currently doing so to try out image and video search. It should be noted that these sidebar elements are currently collapsed by default, which may lessen these impacts.
There are quite a few other minor changes to the interface and some new features, which we will be looking to examine in more detail after this new version of search goes live worldwide over the next 24 hours. There are some rumours that this update coincides with the move to the new 'Caffeine' index, and we are currently witnessing different sets of results on an IP that has already has the new look and feel in place. This is something that we will closely be monitoring over the next day or so.
Personally I am quite in favour of the changes to the look and feel of the site, I feel it gives more power to the average searcher. I think these changes may also help to show more people that there is a lot more to search marketing than just getting a high ranking for a keyword.