Quite a few people have asked whether our apps are compatible with OS X 10.8 Mountain Lion or not. As we are always updating our apps quickly for any new OS X release if there are issues we didn’t find it worth mentioning. But, just in case: There are some smaller issues of especially DEVONthink Pro Office with Mountain Lion, e.g. the not functioning Mail plugin (see below). But all in all all of our are working also on OS X 10.8. We will publish maintenance updates for all our apps, which will, of course, be also properly signed and so produce no Gatekeeper warnings.
BTW: The Mail plugin can break with every OS X update. Apple decourages writing plugins for Mail and so deactivates them automatically every now and then.