Proper SaaS architecture is critical to preventing events such as the recent loss of data from the T Mobile Sidekick Microsoft Danger incident. This is especially important when data loss is involved. When you are running a SaaS operation, it is important to realize that the customer is paying for you to do the innovation, for you to keep the system running, for you to ensure that the system is fault tolerant and secure. This is exactly why SaaS is not hosting. Hosting is just running the application just like any other company would…except it is just running in some other data center where the customer doesn't have to see it. SaaS, on the other hand, is about building a whole solution where the systems are up, fault tolerant, and in the event of an incident, every precaution has been made to keep the solution running for the customers. This involves geographic redundancy, mirrors, hot swap, failovers, and all kinds of other technologies designed to keep technology running. Be sure and ask your solution vendor how they are architected and be sure and weed out those vendors who are really just hosted…and choose the real SaaS solution.