New Netsky variant was found early this morning. In our book, this is Netsky.AA - the first Netsky to roll into "double digits". Next one will be Netsky.AB, Netsky.AC etc.

For reference, many large virus families have done this before, including many macro viruses - which typically had tons of minor variants.

The largest malware family ever seems to be Agobot (aka Gaobot or Phatbot), with over 450 variants. Right now the latest variant is Agobot.RO.