So the cuts and changes will happen anyway, despite whatever the promises were, reminiscent of the Murdoch’s promises to the Bancroft family at the time of the Dow Jones (NYSE: NWS) deal. Bloomberg will lay off about 100 staffers from BusinessWeek staff when the deal to buy it from McGraw-Hill (NYSE: MHP) closes, reports WSJ. This would be about 25 percent of the current staff strength. This comes as Bloomberg just announced appointing Josh Tyrangiel as the new editor of the mag.

A small number of those layoffs are happening this week, and rest would happen in spring when staff moves into Bloomberg’s HQs and magazine relaunches. Not much about new plans for online yet.

Updated: Gawker has a memo from Norm Pearlstine to BW staff, outlining the progress so far and changes coming ahead, hinting at these major layoffs.

—Staci adds: When I interviewed Pearlstine the day the deal was announced, he said Bloomberg wouldn’t gut BW, as many predicted/feared, but he didn’t say they wouldn’t cut. What he did say: “There’s just no way coming in, signing an agreement that any responsible person ought to be making judgments about size of staff, amount of severance and so forth.” Still, he had a roadmap: BW’s own internal estimate that 20 percent of the 420-plus staff should be cut, including 55 in editorial. It’s not clear how much hiring Tyrangiel will be able to do.

“A selection process has been underway in many areas. This week, BusinessWeek staff members (except in Europe and countries where local requirements govern the process) will be invited to a meeting (in person or by telephone) to learn next steps. During the first half of the week, meetings will be held with Marketing, Communications & Events; Circulation and Production; Finance; Technology, and Digital. The remainder of the week will be spent with Sales and Sales Development, and Editorial.”