Interactive TV (ITV) is a new TV experience which enables the subscriber to interact with the television content while viewing it. IPTV is a way of delivering TV services to the subscriber through networking methods of the Internet Protocol. Modern TV experience is often a combination of ITV and IPTV.
Currently, I am involved in projects for Microsoft Mediaroom - a TV middleware which is both IPTV and ITV. Microsoft has come up with a technology called Presentation Framework which enables to develop modern, interactive and user-friendly applications that can be run on the TV screen. Apart from the applications, Mediaroom offers some interesting features such as: live TV pause, personal video recording, video-on-demand and various multiscreen scenarios.
If you want to get familiar with Mediaroom experience, you can check the Mediaroom site at Microsoft.
In my everyday job I work also on other interesting projects enabling content discovery, social interaction and multiscreen experience.