It is definitely Skype. I downloaded it yesterday, put in my username and password, and it showed me my online contacts. I could have dialed or texted any of them quite easily.
Of course, I was hoping to use this kind of application while overseas, using a wifi connection to make a call, as I would using a laptop. Apparently this program won't do that with our G1s. So taking the laptop along will be necessary after all. Not a huge deal, it just would have been handy on the G1.