Unlike mobile and PC access, the use of internet sites through the TV has been small, mostly due to the poor user experience of many "web on TV" deployments, and the "walled garden" or closed business models adopted by many TV network operators.
With the advent of IPTV and Broadband enabled TV Devices web site owners have realized, that like Mobile, TV needs to be considered as a different media, and that Mobile, TV and PC based internet access all require particular user interface design challenges in order to make the services usable, and acceptable to consumers on the device they are using.
The following styles of interface are often considered:
Typically these are characterized as follows:
TV Sites can be developed and deployed using a number of different technologies including Adobe Flash, WTVML, Java and HTML, although the same design principles apply whatever the development technology.
Typically TV Sites are differentiated from web sites by having a "wtv." rather than a "www." sub-domain.
Ashley Highfield (Director of New Media Technology at the BBC) mentions these types of interfaces here in his CES speech.
Microsoft's "Online Spotlight" for Media Center PC was an early example of the ability to deploy TV Sites to Broadband TV devices, as reviewed here