Now, the items underneath Advanced Options have been categorized. Each category can be expanded and collapsed using the +/- symbols. Additionally, all categories can be expanded/collapsed at once using the "expand/collapse" links next to the title "Advanced Options".
Some noteworthy changes:
- The Plain Text Message field has been moved to the top.
- The Tracking options are now below the Plain Text Message section
- The Mark as Template checkbox has been moved to the Miscellaneous section.