The native resolution still says 800x480. There is probably a built-in video scaler like the ones found in a plasma display that makes the 800x480 LCD display all the way up to 1600x1200. However, at 1600x1200, so many pixels get dropped that you won't even be able to read anything. 1600x1200 or 1280x1024? It doesn't even matter because you are not gonna use those two resolutions on a 7-Inch screen anyways.

800x480 native resolution is really high though. That is equivilent to 2400x480 if you use the same method that many other companies use to state pixels. When you see a 7-Inch screen with a 1440 x 234 resolution (for example, the popular TM-701L that digitalww sells), it actually has a native resolution of 480 x 234. They are counting each sub-pixel (R,G,B) as seperate pixels. Why are companies doing this? Well... because consumers like to see high numbers.