Steve jobs has a tendency to identify technologies which are on the brink of succeeding, and bring them to the mass market. Examples are pixar, the iPhone, the iPad and early exclusions (apple was the first to exclude floppies from their computers, and optical drive with the MacBook air)

In that sense it is only natural for apple to enter the robotic market. And with apple's secrecy, they may already be in it.

It will be very exciting if they will release a general purpose robot, with an app store, of course. I can just imagine paying $4.99 for the back massage app, and $0.99 for the fart app :)

Another positive effect that would happen if apple enters this market, is that all the tech companies will follow, and the technology will enter a rapid development stage, as the smartphones are in today.