Lync the communication solution from Microsoft for professionals is going to be integrated to Skype and will be renamed to Skype Professional.
Gurdeep Pall, Skype and Lync vice-president at Microsoft, published a blog article in which the merge is detailed.
In summary, the Lync users will get a Skype interface and will be able to communicate (including via video – new thing) with Skype “non professional” users. The change is planned for the first semester 2015.