There isn't much 4K content on Netflix, but for the handful of shows and movies available in Ultra HD, the company has just made it more expensive to access those 3840x2160 streams.
For those who already have a 4K-enabled Netflix account, your subscription cost won't change until August 12, 2016, but for new subscribers, or current subscribers who haven't enabled 4K content, the monthly cost will be $11.99. This is up from the standard $8.99 for most new subscribers, which only went up in May from $7.99. So Netflix has effectively increased the price of its 4K content by 33%, but doesn't have much to show for it.
Netflix currently hosts Breaking Bad, House of Cards and a few movies in 4K, so I don't see many jumping into the 4K subscription right now.