Apple has updated the Mail app for OS X Mavericks with a few fixes.
- Fixes an issue that prevents deleting, moving, and archiving messages for users with custom Gmail settings
- Addresses an issue that may cause unread counts to be inaccurate
- Includes additional fixes that improve the compatibility and stability of Mail
Previously I reported on problems using Gmail with the Mail app on Mavericks and some people are even ditching Gmail due to the issues with Mail app.