If they figure out the same technique, I don’t see why not. The biggest advantage I see would be getting round the limitation image editing software has of loading entire textures into memory. In Photoshop, you’d only be able to open about a 10,000x10,000 image on most people’s machines if even that.
Image editing should be like editing files in a hex editor. It only opens the segment you need and it does it instantly with very little memory use. If you open a 10GB file in a text editor, it would never load. If you open it in a Hex editor, it pops right up and you can start editing - immediate edits only happen if you don’t change the file size, otherwise you’d have to write the whole 10GB again. This is how most people edit images - the resolution wouldn’t change much, just the contents.
I think this may have implications for games consoles too. I know Carmack said the support will be there for the PS3, Mac, PC and 360 (no Wii initially though because it’s not powerful enough) but I bet they’ll hit the 360’s 10GB space limit pretty quick if that one scene they demo’d had 20GB of textures. The PS3’s Blu-Ray discs will cope with much more.