Looks like we've all got to wait a little bit longer....
From the article:
Valve's Doug Lombardi told CVG today that Half-Life 2: Episode Two's release has slipped from Q1 2007 back to summer 2007. Lombardi told us that the super developer is "now targeting summer 2007" for a release. This obviously affects Team Fortress 2 and Portal, which all form part of mouth-watering Episode Two package.
The title was originally expected to hit at the end of 2006, with Valve confirming back in August it had changed its mind and was instead gunning for Q1 2007, maybe February.
The reason for the further delay to summer 2007 hasn't been given, but we imagine it's simply the case of Episode Two, TF2 and Portal being massive, and requiring extra development time.
News source: CVG