The Wrap‘s Sharon Waxman reported last night that William Morris toppers Jim Wiatt and Dave Wirtschafter announced to staffers Thursday morning that the rumors about an Endeavor merger were true.

“They said they were sorry they had not been more communicative, and that they still don’t know if it’s going to happen,” Waxman writes, quoting “[a] person who spoke to someone who’d been in the room. “It was idiotic not to say anything before now.”

Waxman is understandably perturbed because, as she writes, “I recently wrote that I believed that a merger wasn’t in the offing. It’s what I had been told by senior sources on each side, despite the acknowledgement that talks have proceeded on and off for the past many months. A senior person at one of the two agencies told me that he knew of the talks, but didn’t think it would be completed because the culture of the two agencies were so very different.

“A merger is still not guaranteed” and yet “talks are underway. Joe Ravitch of Goldman Sachs is apparently representing Endeavor, and Ron Olson of Munger Tolles is apparently representing William Morris.

“‘I know enough only to believe that they would really like this to happen,’ said one individual who will be affected by the merger. ‘I’ve no clue about the Ari (Emanuel) of it all, or Patrick (Whitesell) or Adam (Venit). If they’re talking, they’re serious. Yet there has to be some degree of difficulty.’

“Many degrees, in fact — some psychological, some legal. Much has been written, and more will be, about the clash of cultures that will ensue should bowties-please William Morris consummate its union with testosterone-heavy Endeavor.

“‘There’s the wedding,’ said one wag, ‘and then there’s the marriage.’

“Everyone in Hollywood remembers that Ari snuck files out of ICM in the dead of night, part of starting Endeavor back when Jim Wiatt was at ICM. “They were never close,” one former colleague recalled today. A senior film executive who was once an agent said he thinks that a merger will result in a period of turmoil, and lots of opportunities for competitors to poach clients and gain market share.

“‘If I were still an agent, I’d be thrilled,’ said this executive. ‘Lots of partners, egos, people who want their name on the door. If I were an agent I’d be very happy. I’d make mincemeat out of them in a week.’