I have one of these, and I have to say it's pretty cool. I've been growing/harvesting the herb kit for about 5 months now. The purple basil is really awesome, cilantro and parsely are great, dill was a slow starter but has really taken off (although I havn't found a ton of uses for dill), mint is growing but I don't really use the mint too much, and the chives were a dud from the start

I've started experimenting with some flower seeds in the pods that have died (chives and cilantro) and they are sprouting. I think it is about time to start a fresh batch (There is a bit of mold on the base of the plants, and the entire unit could use a good scrubbing) Salad greens are up next. I am going to try and transplant the purple basil to some soil because it is that good.
Overall it is an extremely easy way to grow stuff. It's inspired my to look into some compact fluorescents with full spectrum bulbs (this thing is like the Mr Beer of indoor gardening- good for what it is) It's a bit pricey compared to compact fluorescents, and the seed pods are expensive (they're about $25 per kit)
PseudoChef: I have two cats that will also eat anything. When I first started growing I put some aluminum foil around the area with the plants and gradually removed it. They got used to it after a little while (Although I do have to tape the slot where the water goes in, my one cat has a water fetish)