Since recent upgrades to WP 4.0.1 and Ata 3.7.18, I cannot modify Page titles.
I can change the title in the Page editor, and it shows as changed. But when viewing the Page itself, the title remains as it was.
This applies sitewide.
Go to http://www.pacificroyalties.com/library/key-licenses/
The Page title is "Pacific Royalties Acquires Key Licenses".
But in the Editor, I have modified it to be "Press Release 12-01-14"
See attached screenshot.
Of further interest: the Menu entry for this page is being modified correctly, but not the Page title. On the site, hover over the "Library" on the top menu; you'll see it is correct, "Press Release 12-01-14"
I reported this to the forum at wordpress.org, and they suggested I contact you, because they have no solution.