Even if you're thinking HD resolutions or 2k for RED, here's why I think 4k is the way:
1) Longevity: Get a nice shot in 4k and it will last years for stock photography. A programme made in 4k will be salable for many years to come.
2) Quality: There's no substitute for quality and that's what 4k gives you. On big screen, it's simply stuning.
3) Reframing: If you're doing an HD or 2k production, you've got lots of room to reframe and zoom with 4k.
4) Oversampling: Going down to HD? Now you're oversampling which is always great for image quality.
5) Unique Selling Point: Need to differentiate yourself from your competitors? Then shoot 4k when they're still stuck in HD.
Anyone have any more good 4k uses?