Merger Will Be a Case Study In Ego Management

Now comes the hard part.

William Morris and Endeavor exchanged rings on Monday, and the honeymoon is sure to be wonderful.

And why wouldn't it be? With a client list like that -- Denzel Washington, Russell Crowe, Tina Fey -- and massive amounts of Hollywood mojo, people on both sides will be going through a transition that will take the newly formed WME Entertainment to the top of the agency heap, both revenue-wise and volume-wise.

But remember, marriage is really hard.

To say there's a culture difference -- in leadership style and history -- is an understatement. Simply, William Morris is still making money from "The Dick Van Dyke Show," while Endeavor is younger than, say, Shia LaBeouf -- one of WME's shared clients, by the way.

And that's not an easy thing to dismiss.

At least they do the same things. As talent agencies, both are familiar with the end game. In other words, it's not as pronounced a difference as, say, when the new-media world of AOL merged with old-guard dinosaur Time Warner.

But talk about a board full of personalities. The collective smarts of everyone involved is sure to lead to some hugely successful decisions, but the process by which everyone gets there could be very tense. What happens when Jim Wiatt and Ari Emanuel disagree ... strongly?

In the meantime, the staffers on both sides have a lot to keep them on edge. One person inside the agency said the mood is terrific ... or it's not, depending on who's talking. "On my floor, everything's great," he said. "But obviously, people not involved with the decision don't know what to think."

Indeed, just the basics are hard enough to predict. Who stays? Who goes? William Morris heavy hitter David Lonner is already leaving. So is Endeavor's Tom Strickler.

So what's going to happen when the consolidation really begins?