PCI past was all about how big companies were hit by hackers or others that stole large amounts of credit card data. “It couldn't happen to us because we are such a small company no one would bother” was the way smaller retailers felt about PCI.
PCI present tells you that is exactly what is happening. There are breaches of small businesses happening every day and these businesses are spending large amounts of hard earned cash to diagnose incidents, cover fines for being non-compliant and the actual losses of the card holders. In a Wall Street Journal article in 2005 over 80% of the data breaches have been small businesses.
PCI future: hopefully all retailers, big and small, are currently PCI compliant. The PCI rules change periodically so it may be wise to review your status with any new rules that become effective. If you are not PCI compliant today or if you are not sure about your software's PCI status please visit: https://www.pcisecuritystandards.org/security_standards/vpa/