From Justin.tv API Wiki
Returns aggregate stream information for all live channels (possibly scoped by category).
Formats: xml, json
Params: Can include:
- channel, which will limit to those streams
- category (Justin.tv Categories), which would be the same as the name appearing in the URL of its corresponding directory page on justin.tv (http://www.justin.tv/directory/science_tech, http://www.justin.tv/directory/featured, etc.)
- language, which will select only channels in that language. Language is specified as the language code: nl, fr, zh-cn, etc.
Cache: This response is cached for 60 seconds; polling faster than that will yield no new results.
<hash> <viewers_count>65418</viewers_count> <streams_count>1569</streams_count> </hash>
<hash> <viewers_count>2393</viewers_count> <streams_count>141</streams_count> </hash>