I really wanted the iPad mini once I got my hands on one for the first time. It was so thin and light and looked great in white. The pricing was also a factor not to be underestimated, but at the end of the day, the screen was holding it back. It wasn't a big enough upgrade over my N7 to make it worth the investment which lead me over to the iPad 4. Now that, ladies and gentlemen, is a screen to behold. Yes, the iPad 4 is heavier, and more robust, but if you can get past that, the clarity and sharpness of the display will make it worth your while and the pluses of having more processing power and RAM means it will last longer than the mini if you're one to hold onto your devices.
Crazily enough though, if the mini were to get retina (which is a forgone conclusion around here), it might be game over for the competition (though the Nexus on 4.2 is much better than before), and probably even the big iPad as well. Can you imagine the size/weight of the mini with the resolution/power of the 4? Wow.