Once upon a time, data was doing the catch up and voice was the king. Then data took over. Further down the line data and voice started to merge over a common network. Today, you won't find any major fixed line service provider in the world with voice-only offering. However voice still rules in the wireless world. It remains to be seen which generic path wireless operators take with regard to data services.
Asian and North American operators are more inclined towards WiMAX and that is why the regulators in these countries are opening spectrum for WiMAX. Compared to this the European regulators are not so sure just yet. The result is that WiMAX is still weak in Europe. There have not been any major deployments in this region for WiMAX.
European operators typically have more leverage in the market they serve (typcially incumbents) and they usually own a major cellular arm. They want the next wireless evolution to be on the lines of 3G, UMTS, etc. In North America and Asia service providers see more benefits coming from WiMAX which obvioulsy enables Internet and converged services more seamlessly compared to 3G etc. All the cellular options are after all extension of voice networks. Compared to these, WiMAX is a data centric network and it can handle all voice, video and data in a more efficient manner.