Lync is more useful than most know, mainly because of the lack of information about it which I blame on Microsoft. It took me a long time to master all these functions of Lync, even adding external users can be a challenge if both sides do not have external access turned on. Still, I am very happy I can offer it to my clients as a rich feature of SharePoint\Office 365. I am hoping MSFT eventually ties in Skype more intuitively as so many use it already (and it has the ability to edit IM posts which Lync lacks).
This tool can be huge in opening up collaboration. Everything from status (green-yellow-red) to quick information exchanges to desktop sharing to full blown conference room type meetings, with or without video. The tool is an under the radar feature which many companies are underutilizing due to lack of familiarization.
Caladan Consutling, Inc.