According to Adobe, the company worked closely together to test Creative Suite with Mountain Lion. An Adobe technical note says that there are no CS updates needed for the system upgrade.
However, reading down the compatibility list, I note potential caveats with security and plug-ins. For example, Creative Suite 5 and 5.5 aren't signed by the new Developer ID authentication and require a Digital Signature verification method.
Adobe has added the Gatekeeper signing requirements to our currently shipping applications. However, our legacy products created before Mountain Lion's Gatekeeper feature was available are not signed. If you download one of those legacy (unsigned) applications, the Gatekeeper security feature may pop-up a security dialog that warns users against downloading non-signed applications from the Internet.
The note said that future Adobe updates for CS5–6 will be handled through the Adobe Updater, the company's new automatic downloading and installation utility.
The concern over plug-ins concerns Rosetta, which no longer supported in OS X Mountain Lion. Adobe said that Creative Suite 2 is now totally orphaned with Mountain Lion. The worry is that ancient Rosetta-dependent plug-ins as well as some drivers for older printers, scanners, and some input peripherals also may stop working under Mountain Lion since they may require Rosetta's PPC support.
So, it's important to check your entire workflow carefully before upgrading.