Marketed as a home sentry, they may have overstated its capabilities a bit. While it may not be stopping any intruders, it is an intriguing robot nevertheless.
You'll need a full-fledged computer with a broadband internet connection and wireless at the location where Rovio is to be used. The robot can then be controlled by any remote internet-enabled device.
The Rovio sends back both audio and tv-resolution video streamed in MPEG4 format. It has a two-way speaker/microphone setup that allows you to "talk" with entities on the robot-end of the arrangement. It can also take snap-shots and find its own way back to its recharging base. Not bad for $300.
Now...what to do with it? The stand-in for business meeting, "Say goodnight to daddy", and pet-soother all seem a bit of a stretch to me. I think it's best to assume, that you can use the Rovio to take a look around your place (one flat level of it anyway) when you are not there. While a more modest goal, that could truly be useful.
Here's a page with a full description and video of the Rovio robot.