I'm sure that the X.org server will still be available from Ubuntu repositories for many years, it's not like this announcement forces them to change things overnight.
Posted Mar 7, 2013 23:51 UTC (Thu) by drag (subscriber, #31333)
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It's not like Mir is going to be any time soon either. It's more vaporware then anything else. It's going to take them at least a couple years to get it into usable state to were they can even start thinking about replacing Xfree display server.