Google has changed the column name for the "average CPC" to "approximate CPC" in the Google AdWords Keyword tool.
You will only see the CPC prices if you are signed into your AdWords account. However some people thought it went missing.
A WebmasterWorld thread has one Senior member who has been using AdWords since at least 2002 thinking Google removed the feature. But no, it was renamed from "average CPC" to "approximate CPC."
Here is a picture:
Forum discussion at WebmasterWorld.