*****Warning. This is from a preview release******
Not everybody uses the PowerShell ISE as their primary script editor. However, if you do, or if you are using it to quickly edit a script not on your primary workstation then you will be pleased to see that in v3 it now has IntelliSense. In both the Input pane and the Script Editor.
From the Input pane:
This also works for commands in modules not loaded yet, such as Get-NetIPaddress. (See here for more details on that topic)
Look out for an upcoming blogpost on this cool new PowerShell ISE v3 feature