Lync 2013 Persistent chat has reduced the amount of meaningful information on the screen to about 25% of what is used to be in Chat 2010. Eg: On my screen now, I can see approx. 8 unique entries, but on 2010, on the same screen, I could see over 30 entries.
This has (allegedly) made it prettier and aligned it with Outlook etc, but has made it significantly less user friendly, as you have to scroll back through conversations a lot more than you used to, which makes it harder to browse.
It seems MS don't appreciate how business critical this part of Lync has become to our (and I'd imagine other) organisation.
a) remove the whitespace around all the messages, so we can fit more on the screen,
b) make it optional to remove the photos from the Lync window. Social should not replace functional!