The hostile takeover of S1 is now over and the vagaries of assimilation are about to begin as the two companies have come to terms and the S1 board has approved the acquisition. The deal should be completed before the end of the year. ACI has acquired a team and a software capability that’s proven to be a strong competitor for its own payment transaction switch. S1 has a very supportive customer base and ACI will need to be thoughtful as it makes choices about which platform to emphasize and when as well as how it views the S1 staff. The aborted merger of Fundtech and S1 (a battle we will not get to watch) would have made a formidable competitor to ACI. Now ACI will have some work to do battling for the loyalties of S1 customers and employees.