My Good Friend Freek Berson (http://microsoftplatform.blogspot.com/) and an established Remote Deskop Services MVP has created a Technet Wiki Page for Configuring RDS using PowerShell. If you come across any good resources about RDS and PowerShell, feel free to add it to the WIKI Page.

http://social.technet.microsoft.com/wiki/contents/articles/using-powershell-to-automate-the-installation-and-configuration-of-rds.aspx

Happy PowerShelling!