A new update (aka CU1) for the Lync 2013 Client is available: http://support.microsoft.com/kb/2812461. There is not an associated Lync 2013 Server update yet but stay tuned. Also, this update is just for the Windows Lync Client, not the VDI plug-in and other clients.
This update fixes some bugs (including some presence update issues with Outlook), improves quality, and has some noteworthy new improvements such as the ability to hide offline contacts in your contact list, and improved handling of devices that have both a front-and-rear facing camera.
The download links are at the bottom of the KB article. You will see two installation packages: Lyncloc and Msores. You will need to install both packages.
Also, in case you missed it, there were significant new updates for Lync for Mac 2011 released in recently in January: Update for Lync for Mac 2011: January 2013.