Sideshow has announced the "Shaak Ti VS General Grievous Diorama" which will be ready for pre-order next week. No details on price and estimated shipping dates are available yet. We will have to wait for the product reveal next week for more information.
While this piece really looks good from the preview picture, I am unlikely to purchase it as I generally do not collect dioramas due to their smaller scale. But I am sure that there are many Star Wars fans out there who will be lining up this piece for a place in their collection! :-)