Respond is a mobile-first, responsive theme based on the Omega base theme.
Respond works in three size modes: mobile, fluid and 1200px maximum. Images scale using the fluid images method. This theme is meant to be a proof of concept on some CSS3 features in Drupal as an Omega subtheme. I expect there will be lots of bugs to report, as little to no IE testing was done, and at a certain point, the gradients went a bit wonky and took on a life of their own.
The recommended setup for this theme is a Primary Menu of 6 items. If there are more (or less) it will kind of break the navigation bar in both "normal" sizing and on the mobile version the rounded corners will be a bit wonky potentially.
It is best (when using images in your nodes) to set your primary image style to be a width that is equal to the MAXIMUM that your content area will ever be. So if your content is full width in certain situations, you'd want your image style to be 1200px wide. The image(s) then scales down appropriately based on the size of the containing element. If you are using one or multiple sidebars in your primary content area, you can take those widths into account, and make your "maximum" image preset size to use (on generic node displays AND in views displays) and set it accordingly.
I look forward to getting a bit of usage on this theme, and getting feedback for the overall concepts (make sure to check it out on your mobile device).
This is a community project, and will receive little attention moving forward without the help of the Drupal community. I hope to publish a short video on the quick overview of some of the basic setup and options available to turn off certain CSS elements.
Download Respond and Omega today for your next Drupal 7 install!