We experienced a "mystery" of apps missing issue since 3 weeks or so. We have also noticed that some other app developers are suffering from the same issue. As soon as we found a solution yesterday to take back our disappearing apps, we decided to publish it here, hoping to help someone in the same case.
The context is that our apps (around 20) were missing from the Android Market client on mobile phones, but always present on Android Market's web portal. We finally made them back yesterday by simply clicking "save" button again for each app in our android developer's account. We think the issue might have a relation of the recent upgrade of the android market, concerning developer's account setting-specific, like the locations settings, etc. And a simple refresh might resolve the problem.
some more information that could help,
1. we carry on our search test on China mainland.
2. this kind of "save" button solution works for Android OS 2.2 and above
3. for Android OS 2.1, we did not have our apps missing issue
Above all, we have reported the issue and solution to Google Android Support team, hopefully it would help them to investigate the issue more easily. We have also written an article
above it, hoping that could help someone