Shape let us know that they are testing out a beta of IM+ Talk for BlackBerry which will enable Skype calls over 3G and EDGE networks. They currently allow for half duplex (think walkie talkie) calls over Wi-Fi but the new version is testing those same calls over your 3G and EDGE connection. I am not sure if EDGE data is enough for a solid phone call but who knows.
There is a growing number of VoIP apps for BlackBerry which allow for full duplex (normal phone call) calls so I am hoping IM+ will add that in the future. We have yet to see a Skype client for BlackBerry that actually works over data networks instead of the sham VoIP Verizon is using.