Update 9/29/11: I have been using that app for a month now, and it is simply not stable; Finder crashes regularly while F-Secure is running. This application is not ready. Notably, F-Secure has removed "Lion" from its requirements list since I last posted. Use another application until F-Secure releases a definitive statement on 10.7 compatibility.

I spoke with support on August 24, and they said Anti-Virus for Mac was now compatible with Lion. The product page (listed above) also lists 10.7 as a requirement. The install was not without problems, though. When I attempted to input my license key after installing the app, all open applications crashed including the Finder and OS X became unresponsive. I restarted and the application would not run launch in the Menu Bar as it normally does. I called support, and they re-affirmed Lion support. The technician directed me to restart in 32-bit mode and allow the "install to finish" (the technician's words, not mine). This time, I logged into an administrator account and the application launched properly. However, I had to manually click "turn firewall on" in the Status window even though the firewall was already enabled on my machine. I restarted in 64-bit mode, and it appears to be functioning properly without further issue. I would recommend caution installing this app on 10.7, because it does not seem quite ready for Lion.