Office Web app Server

One of the new things thats comes with Lync 2013 is Office Web App Server.
So what is this, and that is a good question to ask. Do I need this??
This is a part of the topology builder and it ask you if you have a Office Web App server already running in you network. If not, well then you have to install a new one if you want.

From the deployment document we can read this:
http://technet.microsoft.com/en-us/library/jj204792%28v=ocs.15%29

In Microsoft Lync Server 2013 Preview PowerPoint presentations were viewed in one of two ways. For users running Microsoft Lync 2010, PowerPoint presentations were displayed using the PowerPoint 97-2003 format and were viewed using an embedded copy of the PowerPoint viewer. For users running Lync Web App, PowerPoint presentations were converted to dynamic HTML files then viewed using a combination of those customized DHTML files and Microsoft Silverlight. Although generally effective, this approach did have some limitations:

• The embedded PowerPoint Viewer (which provided the optimal viewing experience) is only available on the Windows platform.
• Many mobile devices (including some of the more popular mobile phones) do not support Silverlight.
• Neither the PowerPoint Viewer nor the DHTML/Silverlight approach support all the features (such slide transitions and embedded video) that are found in the more recent editions of Microsoft PowerPoint.

To help address these issues, and to improve the overall experience of users presenting or viewing PowerPoint presentations, Lync Server 2013 Preview employs Office Web Apps and the Office Web Apps Server to handle PowerPoint presentations. Among other advantages, this new approach enables:

• Higher-resolution displays and better support for PowerPoint capabilities, such as animations, slide transitions, and embedded video.
• Additional mobile devices to access these presentations. That's because Lync Server 2013 Preview uses standard DHTML and JavaScript to broadcast PowerPoint presentations instead of customized DHTML and Silverlight.
• Users with the appropriate privileges to scroll through a PowerPoint presentation independent of the presentation itself. For example, while Ken Myer is presenting his slide show, Pilar Ackerman can look at any slide she wants to, and without affecting Ken's presentation.

But there is more, you can use Sharepoint2013 to communicate with Office Web App Server. So there might be a good way when RTM comes out to start to plan for this environment.
I have not found any "server spesifications" yet, so if anyone out there has something please inform me...........