Version: Service Pack Hot Fix Date Server Seq Client Notes
5.0.129.0 Beta 2   July 11, 2012 I I I First Public Beta Version for 5.0

Was only available via Microsoft Connect. No longer available for download.

5.0.0.536 was the initial beta for 5.0 made generally available to the public. The release was distributed using Microsoft Connect, requiring signing up and requesting the download, which appeared to be a formality to track usage as well as to encourage using Connect to provide feedback to the beta release.