That would be a milestone. They're already talking about 2 gigahertz chip speeds, so at this point I'm open for just about anything. It makes me think about the beginning of this century. The automobile was one of the hottest things going, and although crude at best, it was revolutionary. Sure it was an expensive luxury only enjoyed by the elite individuals who had money to burn, but by the end of the century it has become one of the singular most important items in daily life.
Most families now own at least one and many have several.
The cost has come down dramatically while the features have grown exponentially. The computer is already on a path to overtake the automobile in terms of ubiquity and importance. Although not everybody has one yet, many of those that do have more than one. Consumer level computers didn't exist 30 years ago let alone at the beginning of the century. In fact, the craze didn't really get jump started until a decade ago.