Microsoft has released an update for Lync 2013 yesterday that corrects multiple issues but most notably it improves sharing performance. The actual increases are still to be determined by myself, but I can also note conversation taskbar icons have changed as well. Before I recommend the latest patch I am going to run with it for a short while. J

One interesting note from the KB article is you may or may not see the correct version number post install. Why? Great question but the note states: “After you install this update, the Lync 2013 version may not be displayed correctly as15.0.4605.1003. Instead, it may be displayed as an earlier version, such as15.0.4605.1000.”

There are four pre-requisites for the Lync patch (this has not recently changed) which include MSO (KB2727096), MSORES (KB2817624), IDCRL (KB2817626), and Lynchelp (KB2817678).

Additional Notes: 
Lync Server 2010 build number is 4.0.7577.225
Lync 2010 Client build number is 4.0.7577.4419
Lync Server 2013 build number is 5.0.8308.577
Lync 2013 Client build number is 15.0.4605.1003
Lync Group Chat build number is 4.0.7577. 4409
Lync Group Chat Server build number 4.0.7577.4409
Lync Group Chat Admin build number 4.0.7577.4409
Lync Attendee build number is 4.0.7577.4356
Lync Attendant build number is 4.0.7577.4098
Lync Phone Editions build number is 4.0.7577.4420
Lync 2010 for iPhone build number 4.7
Lync 2010 for iPad build number 4.7
Lync 2010 for Android build number 4.0.6509.3001
Lync 2013 for Windows Phone build number is 5.2.1072.0
Lync 2013 for iPad build number is 5.2
Lync 2013 for iPhone build number is 5.2
Lync 2013 for Android build number 5.1.0000
Lync Basic 2013 build number is 15.0.4420.1017
Lync VDI 2013 build number is 15.0.4420.1017