USB is slowly approaching "single cable" solution. By adding power, USB3 and Thunderbolt are two differentiated solutions moving towards a similar goal.
While they are both "single cable" solutions, their differences give them different uses. Currently there are lots of cheap USB gadgets, and you probably have lots of USB cables floating around your house. Thunderbolt uses active cables, which means the cables contain hardware to code the signal specially for that cable. This allows much better guarantees of throughput, while making cables much more expensive. With this in mind, I think we are likely to see thunderbolt used in more 'dedicated' scenarios, like removable harddrives, displays, and printers. Daisy chaining means you don't need many ports either.
On the other hand, USB cables are cheap, but have less guarantees on throughput. In fact, since many ports could be on one hub, you can't even use all ports to there maximum potential. USB is likely to stay in its current position for the foreseeable future though.