* new ways to view search results: using specialized snippets, on a timeline or on a map. You can also access this feature without joining the experiment, using the view operator: just add view:info, view:timeline or view:map to your query. Example: [tory amos view:timeline]. This is the most innovative experiment, but it should be better integrated in the user interface and offered as an option only for some of the queries. (Update: This view has a new feature described in a future post.)
* keyboard shortcuts: select a search result or move to the next result without using your mouse. You'll like it if you use shortcuts in Gmail or Google Reader, but it's hard to understand why Google thinks that the ads placed at the top of the page are search results.
* two similar experiments: put the search navigation at the left/right of the page. This is somehow similar with Ask.com's new interface and Yahoo's search assistant because it makes it easy to explore a domain and provide better queries.
You can only choose one experiment at a time, it's easy to switch between them or deactivate them and there's an option to send your feedback. I'm still undecided between the keyboard shortcuts and the left-hand search navigation, so it would be nice to choose two or more non-conflicting experiments.