When a competitor acquires one’s customer(s), keep an eye on their usage. Common sense would dictate the newly acquired customer would quickly transition to a new service provider. If the acquired customer does not part ways, this would allow for some interesting marketing / pr material. Better yet, when the competitor renews the contract, make sure to take note of the renewal. One could use the renewal in aggressive marketing.

A lovely case study: SAP becomes NetSuite’s latest customer.

http://www.enterpriseirregulars.com/48979/netsuite-runs-sap/

http://www.zdnet.com/blog/saas/successfactors-swaps-netsuite-for-bydesign/1561