Google Custom Search Engine (CSE), just announced a new results style calling it more modern and streamlined, which is based on the evolving Google+ design and experience across Google properties.
"This look will be the new default for new custom search engines, and admins of existing custom search engines can also choose this new style by visiting the Look and feel page of their CSE's control panel and selecting "Default" in the Choose or customize a style section," informs Google.
The old default remains an option, but has been renamed to "Classic".
In addition to the new style for results, Google is also updating the CSE search box, which now comes with more robust and consistent "autocomplete" with the standard Google autocomplete.
Note: The autocomplete update affects all CSEs that use the Element, in some rare cases, "site owners who have made customizations to their CSE search box (or who have enabled autocomplete for their own search boxes) may need to make minor updates to accommodate the new search box's slightly different look," Google said.