Your best bet is to go on AppBrain.com and search for the standard video chat app, Qik, and then take a look at the related apps. You won't find a compiled list of all the video chat apps, in fact, you wont find a compiled list of many subcategorized apps. I think the closest thing you can get to reduce searching around is on AppBrain, at least there you can see other users reviews and get basic info on the app. Cross-compatibility will definitely be needed so the app will need to have full website support as well. That should be the foundation of your search.
Your best bet is to check out each app, read the reviews, check out the developers website, and look through the applications settings manually.
And then if you'd like, you could possibly create a Video Chat GoTo Guide that i'm sure the moderators would love to sticky in the Applications Forum.