Here, to prove my point:
That is as much information as has been released so far.
http://forums.steampowered.com...howthread.php?t=475909
Will the game be released on its own?
No. Valve unveiled Team Fortress 2 and Portal, two new games to be included in Half-Life 2: Episode Two. In addition to the previous, Half-Life 2 and Episode One will be included as well. The name of the bundle is Half-Life 2 Orange Box and it is the only available way to purchase Episode Two, as far as retail is concerned. Steam will probably offer Half-Life 2: Episode Two, Team Fortress 2and Portal as a package or even Half-Life 2: Episode Two on its own, although specific details have not been made known.
That is as much information as has been released so far.
http://forums.steampowered.com...howthread.php?t=475909