We do have a PowerPoint slide prepared by Pam Misialek which provides details of all the features which are available with the first release of the GP 2013 Web Client. The link for downloading this slide deck is attached at the end of this article.
The second release of the Web Client is also in progress and is planned to be released during March/April timeframe. This release will include the HR and Payroll functionality built into it. That’s good to hear!