I highly suggest you check this Orange Box video out. It shows all three new games in the Orange Box, and shows off plenty of Episode Two. There's even a new blood system for Gordon! It looks really nice. The video is on the 360, but its really cool. The first video appears to only cover Episode Two, but a second video nearby shows off Portal and TF2.
Episode Two Hands-On Video/Interview GameSpot Video: Half-Life 2: The Orange Box Stage Demo
Portal and TF2 Hands-On Video/Interview GameSpot Video: Half-Life 2: The Orange Box - Team Fortress 2 - Portal Stage Demo
Get full, we have 2 months and 18 days left until release. At least us in America.