/usr/libexec/java_home
/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home

ls -l /usr/bin/java
lrwxr-xr-x  1 root  wheel  74 22 Jun 09:53 /usr/bin/java -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/java

ls -l  /System/Library/Frameworks/JavaVM.framework/Versions/
total 64
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.4 -> CurrentJDK
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.4.2 -> CurrentJDK
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.5 -> CurrentJDK
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.5.0 -> CurrentJDK
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.6 -> CurrentJDK
lrwxr-xr-x  1 root  wheel   10 22 Jun 09:53 1.6.0 -> CurrentJDK
drwxr-xr-x  8 root  wheel  272 22 Jun 09:54 A
lrwxr-xr-x  1 root  wheel    1 22 Jun 09:53 Current -> A
lrwxr-xr-x  1 root  wheel   59 22 Jun 09:53 CurrentJDK -> /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents
As you can see, this is pointing to a 1.6 VM
sudo rm CurrentJDK
sudo ln -s /Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents CurrentJDK
If necessary remove the plugin info and reinstall Java
cd /Library/Internet Plug-Ins/
sudo rm -rf JavaAppletPlugin.plugin