Early this month Google announced that they were going to move encrypted search from https://www.google.com to a new hostname because school authorities were having trouble keeping students off adult content. The transfer was completed last Friday.
The new location for encrypted search is now https://encrypted.google.com.
Previously, school administrators who wanted to block encrypted searches at https://google.com would also block other Google authenticated services such as Google Apps. School authorities can now block encrypted search without affecting other Google services that require secure connections.
Google says that are still exploring better solutions so that encrypted search could be returned to https://www.google.com.