Conduct a competitive takeout
Gribodemon initiated the competitive takeout method as a means to make it easy for Slavik's customers to switch to SpyEye. In a bit of back-and-forth, Slavik employed the same method in response to Gribodemon's takeout campaign, making it easier for each other's customers to switch back-and-forth.
Conduct a competitive upgrade
To capitalize on the success of the actual ZeuS botnet functionality, Gribodemon took advantage of the ZeuS configuration, giving the new customer immediate access to all of the hooks, knowledge, and connections the ZeuS botnet had already gained through its host.
Tough market? Change it
Experiencing pain coming from two sides--the competition and the customer--Slavik saw there was a need to change the game. To do this, he handed the expensive and exhausting customer support over to Gribodemon and changed the delivery model of his product from a perpetual kit to software-as-a-service. This forced Gribodemon and the rest of the players to chase a new horse.
Keep your friends close and your enemies closer
With the market's two leaders now on the sidelines, it will be interesting to see how new business leaders, new businesses, and new technologies will surface, battle each other, align with each other, and ultimately drive each other to the legal edge. Until that story is written, I suggest the world's financial institutions continue to beef up their anti-fraud programs to protect their systems--and their money--from these bots.