OK - I really, REALLY want Skype for the Blackberry (Tour) which I had on my iPhone (when I had an iPhone). That app worked very well. I was able to make calls @ .07 cents per minute from the iphone in the US to my daughters cellphone in Russia and make calls from my iPhone while in China back to a landline in the US for approx that same .07 cents!
I have Google Voice for the Blackberry, runs fine on my new Tour. I have a Google Voice account and phone number. I've been able to use GV on the Tour to send no cost text/SMS and calls from the US to overseas are approx .02 cents to .05 cents per minute.
Before I go to China on business in 3 weeks, I would love to hear from anyone who has used a Tour or other BB with Google Voice while roaming overseas... were you able to use GV while on GSM networks to make low cost calls back to the US???