Netflix stock shot up more than 13% Thursday, hitting an all-time high of $541.43 per share in early trading, after the No. 1 subscription-video player packed on about 860,000 more streaming customers than expected in the first quarter of 2015.

The company added 4.9 million streaming subs worldwide in the period, including 2.28 million in the U.S.

Netflix’s big stock move gives it a market cap of more than $32 billion, making it more valuable — at the moment — than media companies including CBS, Viacom and Discovery Communications.

[UPDATE: 5:30 p.m. ET: Netflix shares closed at $562.05 per share Thursday, up 18% for the day. The company now has a market cap of about $34 billion; that makes it more valuable than Twitter ($33.2 billion) and Dish Network ($32.5 billion). Overall, the markets were down slightly Thursday.]

“Overall we view Q1 domestic streaming results as emphatically positive — exceeding revenue estimates and (perhaps more importantly) materially beating net sub adds expectations,” RBC Capital Markets analyst Mark Mahaney wrote in a research note.

With about 41.4 million U.S. subs and 21 million international customers, Netflix is “one of the largest global entertainment subscription businesses,” Mahaney added. “We believe that Netflix has achieved a level of sustainable scale, growth and profitability that isn’t currently reflected in its stock price.” The analyst maintained an “outperform” rating on the stock, with a price target of $600.

Netflix, for its part, attributed the strong subscriber gains to its growing programming lineup, including the Q1 launch of “House of Cards” season 3 and new shows “Unbreakable Kimmy Schmidt” (pictured above) and “Bloodline.” Another eagerly awaited original series, “Marvel’s Daredevil,” hit the service April 10, after the end of the first quarter on March 31.

The company’s original-content strategy is now fueling a virtuous cycle, driving up both gross adds and cutting churn, according to UBS analyst Doug Mitchelson.

“Netflix reminds us of ESPN’s virtuous cycle 15 years ago, when ESPN’s leadership allowed it to acquire more and better sports rights, helping drive strong growth off its leading revenue base and so on,” he wrote in a research note. That resulted in ESPN building an “insurmountable” edge over rivals: “ESPN spends more on sports rights than any other network, and also makes more money on sports rights than any other network.”

On the strong Q1 results, Cowen & Co. analyst John Blackledge raised estimates for Netflix subscriber gains for 2015 and beyond. This year, per his revised estimates, the company will add 6 million U.S. and 11 million international subs (up from the previous 4.8 million and 8.5 million, respectively). The analyst also raised his price target on the stock from $465 to $625 per share.

The most recent quarter stands in contrast to Netflix’s third quarter of 2014, when the company badly missed expectations on sub growth (gaining 3.2 million, 670,000 fewer than it had forecast). That pushed the stock down as much as 26%.