Java 8 JDK final got released today so time install!
Add the PPA:
Update and install
Using the correct version? If you have java-7-orcale, java-7-openjdk, etc installed on your machine you now need to make sure the default is set to java-8-oracle. This will list all the installed options for Java:
This will let you chose the default version of Java to use:
That is it lambda time!
UPDATE:
There is a much better way to change the default java version. This will change the compiler (javac) and other executables also to be Java 8.