London to Sydney in less than five hours

It could happen one day, if the designers of a hypersonic plane have their way: http://news.bbc.co.uk/1/hi/england/oxfordshire/7228341.stm. I admit, I am an incurable technology geek, and stuff like this really intrigues me. If the sound issues (sonic booms) could be resolved, could this plane be used over land? Could we be looking at a flight from New York City to Los Angeles which lasted only a half hour or so? Montreal to Moscow in two hours? The possibilites (and the daydreaming) are endless..............