Apple accidently indexed the file Safari7.1MavericksSeed.pkg in the file
index-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
giving ALL the public with mavericks access to it.
They should have only put it onto the developer and public beta testers index files.
It should not go onto
index-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
until safari 7.1 is actually officially publicly released.
This would explain why you are seeing it in your mac app store even if you are not a developer or public beta tester.
I put a message about it in apple's developer forums and apple acted pretty quickly on it and have now removed the file Safari7.1MavericksSeed.pkg from index-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
Hence it is no longer publicly available to everyone. (But is still available to developers via the mac dev center).
