Earlier this year Google added the chat sidebar to iGoogle, which gave you Gmail-style chat in your iGoogle start page. Now they've expanded the chat functionality to include video chat right from the main iGoogle interface.
If you've already downloaded the video-chat plugin when it was released for Gtalk in Gmail, then you're already set. If you haven't done so yet, you'll need to download the plugin here.
Once you have the plugin installed whenever you are talking with another person using iGoogle, GTalk or supported third-party clients or mobile phones, you'll be able to start a video chat with them directly from iGoogle.
Video chat from iGoogle [Google Talkabout]