And apparently, they only announced this last week!! (But to be fair, I guess it's actually 1 euro cheaper than previously if you wanted to see the exhibitions.
http://www.louvre.fr/en/hours-admission/admission#tabs
"As of July 1, 2015, the Louvre will adopt a €15 ticket giving access to collections and exhibitions.
(Following is the OLD ticket information, which they still have on the page.)
Tickets for the Permanent Collections:
€12
Full-day access to the Louvre, except for temporary exhibitions in the Hall Napoléon
also valid for the Musée Eugène Delacroix.
Tickets for Exhibitions in the Hall Napoléon:
€13
Note that free admission to the museum on the first Sunday of every month does not include the exhibitions in the Hall Napoléon.
Combined Ticket:
€16
Access to the permanent collections and temporary exhibitions in both the Louvre and the Musée Eugène Delacroix."