Well, first of all, Qt is anything but new.
The Qt strategy was a good one. However, they pulled the plug before they even started to sell the idea to Symbian or multiplatform developers, so it never got tested in real life.
I doubt that the Qt strategy would/could have done anything good about the inherited flaws in Symbian, but it would do very much for the applications on top of Symbian (and thus, MeeGo).
The "Write once and run anywhere" strategy has made Windows the most used operating systems throughout time. Some applications from MS DOS will still work with Windows 7,
applications will work across virtualbox on cell phones, servers, tablets, tabletPCs, netbooks, pretty much any computer made after the given software were created.
Oh, and while Sun may have stumbled, Android is nothing but a virtualization motor made in a rip-off copy of Java.
So, I think the whole Write once and run anywhere strategy can work very well, thank you vely mush.