Yes, the upcoming next-gen consoles will support 4K (Ultra HD) resolution. But it will be only supported for movies. Unfortunately games will not be supported, you can just play games in 1080p (Full HD) resolution. So you can only watch movies in 4K. But you need a TV the supports 4K resolution otherwise you are not able to watch the highest resolution.
Another problem at the moment is that are only a few sources for 4K movies. There are few Blu-rays in 4K or streaming offers. There are a few movies on Blu-ray available that are “Mastered in 4K” like “The Amazing Spiderman”, “Godzilla” or “Total Recall”. Maybe with the release of the PS 4 and Xbox One we will get more stuff in 4K (Ultra HD).
Buy game consoles here
Xbox One Console- Standard Edition
Xbox One Console
PlayStation 4 (PS4): Standard Edition
Sony PlayStation 4 (PS4)
PlayStation 4 Battlefield 4 Launch Day Bundle
PlayStation 4 Killzone Launch Day Bundle