Here are the complete release notes for OS X 10.10.1:
The OS X 10.10.1 update is recommended for all Yosemite users. It improves the stability and compatibility of your Mac. This update:
- Improves Wi-Fi reliability – Improves reliability when connecting to a Microsoft Exchange Server – Improves reliability sending Mail messages when using certain email service providers – Improves reliability when connecting to remote computers using Back to My Mac.
The Wi-Fi issues were particularly widespread, with a number of users having issues with their wireless connection, myself included. Hopefully this update will once and for all take care of those problems.
Users can download the update directly through the Mac App Store.
OS X Yosemite originally arrived in mid-October featuring a substantial visual redesign and other improvements.