Fring and Skype broke up recently, so I have installed Nimbuzz for my communication needs. It supports a dozen of different messengers, including ICQ, GTalk, Yahoo and, most importantly, it supports Skype calls. Also, Nimbuzz allows to call mobile and landlines with the prices about 15% lower than Skype. I have made only a few calls (over WiFi, not 3G), so I cannot decide if the quality is better or worse, but with Skype Mobile stuck in the permanent infancy, there’s not much choice.
The only problem I found is the permanent 2-3%/hour battery drain, even if the WiFi is down and Nimbuzz is supposed to be asleep. Solution: select Nimbuzz and press “exit” when not using it. The picture on the right shows the battery voltage while it’s running and flat line soon after it’s killed.