This one is easy. It's an easy call that WiFi capable mobile phones will rule and that they will give a hard time to the full implementation of UMTS. Please take notice that we already have stated this in here more than once and are now more than ever, absolutely sure. 

I knew mobile phones would be really big business when I saw my grand-mother using one. I know WiFi mobiles will be big business when I see my grand-mother again trying to learn how to use skype. It’s as simple as that. A winning combination: speaking (what we do best) and free or very low cost!

And mobile phones WiFi capable are now getting to the market. Convergence “oblige”, it would happen sooner or later, with the junction of Internet connection availability, WiFi and an OS capable of running a VoIP application

To better illustrate this, examine the following two articles; from wi-fiplanet, Who Wants a Dual-Mode Phone and from gigaom, The Rise of the WiFi Phones.