Texture fading

Hi there!

I would like to animate a texture in a particular way.
Indeed, I would like to fade from this: http://www.stockme.fr/img616e06807c/sm/1348862407801.jpg to this: http://www.stockme.fr/img14003f16bd/BlenderArtists_post_on_texture_animation_fading.png (those are sample images, not the actual ones).
I want this image to be applied on a plane, and I want the player to be able to see through the alpha hole (on the bag of chips here). So here is my question: is there a way to easily and smoothly fade from the solid texture to the second texture, in order to make the hole slowly and smoothly appears ?
Am I obliged to make a tile map and a frame-by-frame animation? I was planning not to, as the tile map would be huge (considering the image size), and consequently not very performance-friendly.
I tried to toy with texture keyframes, but I did not find anything effective – maybe I’m just not understanding how they work…

I also tried it with Material-keyframing and failed (looks like it doesnt work in BGE).
I think Ive seen a similar tutorial for this a while ago, but Im not sure.
However, you could perhaps try it with a video texture?

Read Fading and Transparency for all Shading modes.
It does not only belong to fading to invisibility it also belongs to fade two textures. Just have a look.

Wow, great tutorial! Thanks a lot!
Although, I don’t understand how you can fade from one texture to another; so I’ve overlaid 2 planes with a different texture at the exact same position and made one plane disappear thanks to Object Color awesomeness and Keyframes. But, was it what you meant by “fade two textures”?