Mine was 1.2 GB yesterday. Then I moved most apps from phone to sd card and it reduced to 500MB. So I guess storage check is not accurate. Other thing I noticed was that the storage check has shown my "System" memory use as 1.9 GB since Amber update. I believe that it would have increased (which could be confirmed by checking storage sense). So the conclusion is it's not accurate and this settings may include some other stuff too.