Yes I decided to use it this evening and though it takes a moment to initialise the voice it works pretty well.
I'm a bit uncomfortable about giving my chat login details to a 3rd party but I made up a new one to test and I must say it works heaps better than I'd hoped!
On the down side, Fring tends to hang at times especially if it's set to launch at bootup. If that's disabled and launched manually once the phone's booted it operates fine.
There's the obligatory 'satellite delay' but a)it's free, b)are there any alternatives out there? c)it looks damn cool, d)did I say it's free?