Yup there is another one but its kinda flaky. Its called KNOCKING LIVE BETA. It works with Droid to Droid or Droid to iPhone. They claim they will add more phones later. Once you download the app, you have to create an account. You can link your account to Facebook and I think Twitter if you want. This app will turn your phone into an instant webcam. Once you contact someone else with the app on their phone it will turn their phone into a webcam and you both will be able to see each other.
The trick is to get the person on the phone FIRST then start up your KNOCKING LIVE app. Once they are both up, continue with your conversation and you will be able to view and talk at the same time!
I have not tried it with a Droid to Droid, but I did try it with a Droid to iPhone and it worked!!
I said it was kind of flaky because I have not been able to get it to work since the first time I tried it out! I have contacted the folks at Knocking Live via their discussion forums on their website and haven't really gotten a good explanation. This IS a Beta app so hopefully they will fix whatever is wrong when the real thing comes along.