It's the one thing TV makers don't highlight when gushing over the colors, detail and sharpness of pictures on their new higher-than-high-def televisions: how consumers can get suitable content into their homes and then onto the screen.
But Japan's Sony might have an answer. Later this week, the TV maker will reveal what it calls "the world's first 4K Ultra HD delivery solution."
4K television is the latest whiz-bang technology from the big-name TV makers. Taking over where 3D failed, companies like Sony and Samsung are hoping the technology will eventually spur a new upgrade cycle in the TV industry.
Televisions featuring 4K screens have a resolution of 3,840 pixels by 2,160 pixels -- almost four times that of today's best HD televisions. The pictures are superb, but so far the technology has existed mainly in flashy trade show booths. Its jump to the living room has been slowed by price tags around US$15,000 and also by a lack of content.
While companies like Sony already make motion pictures at such high resolutions, there's no established consumer delivery format. Blu-ray Disc won't support the higher resolution, and neither will the HDMI interface used on TVs.
That's what makes Sony's promised announcement so interesting.
Sony will soon begin shipping its 84-inch 4K TV to customers who placed preorders, and the TV will offer "pre-loaded, native 4K entertainment."
"Not some goofy 4K content shot as a demo, but full length feature Hollywood productions, and available exclusively to purchasers of the Sony XBR-84X900 television," the company said in a statement.
That mention of "preload" might be a clue. The set could feature a hard-disk drive, with content likely delivered over the Internet.
Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is firstname.lastname@example.org