My rice cooker recently turned out the highest chiffon/sponge cake I've ever made in any appliance including my oven. In answer to your question, my rice cooker is capable of baking a "good" cake, but all rice cookers are not equal, and for sure all recipes are not equal.
Explanation of "good" follows.
My cake's shape slightly resembled a wheel of cheese. I happen to have a pot with a rounded base, and my cake was overcooked so it did not sink upon cooling, creating rounded edges on both top and botton. However I would not have considered it misshapen. If it had not been dark blue (food colouring) I'm sure my guests would have recognised it immediately as a cake. I have seen other rounded-base rice cooker cakes that had flat tops, and flat-base rice cooker cakes with flat tops and bottoms. Presumably if you had a cake-shaped rice cooker pot you could bake a cake-shaped cake in it - whatever you feel that is.
Actual taste is almost entirely down to my recipe, as mentioned by another poster. I chose to ignore the rice cooker recipe which didn't seem right, and use a combination of recipes of bloggers who have made rice cooker cakes, and my own judgment. As far as rice cooker-related taste factors, there was no clear evidence of Maillard reaction in my rice cooker and therefore no caramelisation or burning on top despite being (deliberately) overcooked.
3. Like a cake baked normally
Of course your mileage will vary depending on your definition of normal. My answer is yes and no: yes for the purposes of presenting an acceptable cake and no because there were certainly differences. Some of these differences made the cake better in my opinion than if it had been baked in an oven.
As mentioned my cake rose very high, 2-3x the height of the original batter, and then did not sink upon cooling, something I have not replicated in a conventional oven. I also found the crumb much more even than most of my oven baked cakes, ie no undercooked centre. The texture was soft and moist. It did not have any kind of crispness on top, only a slight membrane.
Overall I consider it was a "good" cake and would make one again.