As NBC Universal execs digested the confirmation of Jeff Zucker’s pending exit, it’s become clear that Comcast’s Steve Burke is poised to assume CEO functions at the conglom.

Burke, Comcast’s chief operating officer, has been a steady presence at 30 Rock in recent months, and execs say he’s mentioned more than once that he’s a “day-one guy,” meaning that he wants to get moving on Comcast’s strategic vision for NBC U as soon as Comcast’s deal to buy 51% of NBC U from General Electric closes.

Michael Angelakis, Comcast’s chief financial officer, is also working at Burke’s side as they examine the ins and outs of the Peacock’s operations and prep for the integration of Comcast’s entertainment assets with NBC U.

Insiders said Burke appears to be focused on realigning NBC U’s business units to streamline some of Zucker’s reporting structures. It’s no secret that conversations are ongoing about the management of the cable group, the single-largest driver of NBC U profit.

The uncertainty of how that management overhaul will shake out under Burke has fueled all manner of speculation about the future roles for Jeff Gaspin, who oversees all entertainment cable and the NBC broadcast net; Bonnie Hammer, who oversees USA and Syfy and the cable production wing; and Lauren Zalaznick, steward of Bravo, Oxygen, iVillage and the Women@NBCU crossplatform ad sales initiative.

The expectation is that CNBC, whose prexy Mark Hoffman has reported directly to Zucker, and MSNBC, managed by NBC News prexy Steve Capus, who also reported to Zucker, will be rolled into the larger cable group.

On the Comcast side, execs who will surely factor into the overhauled NBC U equation include Jeff Shell, prexy of Comcast Programming Group, and Comcast entertainment prexy Ted Harbert. Both Shell and Harbert have TV programming backgrounds. Harbert’s years at ABC make him a natural contender for a role in managing NBC.

Yet there’s also rampant speculation that former Showtime entertainment chief Bob Greenblatt is waiting in the wings to cut a deal with Burke for a top post involving programming and production for NBC and possibly other NBC U units.

With so many players in the mix, the rumor mill at 30 Rock and in Burbank is working overtime on endless exec-shuffling scenarios.

The one area that may remain largely untouched in the near term is Universal Studios, led by prexy Ron Meyer, as Burke appears to be training most of his attention on solidifying the long-term management plan for the formidable cable group — which will soon encompass Comcast’s E!, Style, Golf Channel and G4 — and shoring up the still-shaky fortunes of the NBC broadcast net.

Comcast already had designated Burke as the overseer of its investment in NBC Universal, given his background as an exec at Disney and ABC before he joined Comcast in 1998. But in recent weeks it’s become clear that Burke is preparing to roll up his sleeves and closely oversee NBC U’s distinct units, which would put him in the CEO role even if he doesn’t formally take the title of NBC U CEO. In March, Comcast moved to free up Burke from his duties of overseeing Comcast’s cable systems by recruiting former Charter Communications CEO Neil Smit for the new post of prexy of Comcast Cable.

The timing of Zucker’s announcement caught everyone, including Comcast brass, by surprise early Friday morning when CNBC broke the news, which has now added urgency to the speculation about what’s to come after the merger.

“Anyone who tells you they know what’s going to happen right now is lying,” said one NBC U vet.