With version 0.56+, tags are available in Text Source.  Simply insert those tags in your text and the value will be shown in your broadcast...

Rhythmbox

• #RHYTHMBOX:TITLE
• #RHYTHMBOX:ALBUM
• #RHYTHMBOX:ARTIST
• #RHYTHMBOX:YEAR
• #RHYTHMBOX:DURATION
• #RHYTHMBOX:GENRE
• #RHYTHMBOX:STREAMTITLE
  

System

• #NOW
• #YEAR
• #MONTH
• #MONTHNAME
  
• #DATE
• #DAY
• #HOUR
• #MINUTE
• #SECOND