An XM Satellite Radio spokesperson has confirmed that the brand is in review at the behest of GM/OnStar, whose AoR (Campbell Ewald) has been working on integrating the XM brand into GM's model.

Per spokesperson:

"GM/OnStar is conducting an ad agency review to select an agency to help them integrate the XM brand into GM vehicle and dealership marketing — across all GM divisions. This business had been with Campbell-Ewald since 2001, and Campbell-Ewald is participating in the review.

XM Radio is working with GM to evaluate agencies, but this is not a review of XM's agencies of record, which remain Mullen (for Media) and Lowe New York (for Creative)."

Word from inside CE is XM notified CE that they'd already lost the account, and that as of yesterday a speedy pull out was under way. Learn more about that, and the fallout, after the jump.

More: Campbell-Ewald: What A Hot Mess Looks Like

Here's where it gets juicy. Our spy said the review has already been lost, that it's 100 percent confirmed, and that executive leadership changes are underway as a result. Yeah — a pissed-off GM ain't a good thing, especially when they're all you've got left. (Navy is in review, too, so unless you consider USPS a solid front, GM looking elsewhere is a bad thing.

This review was quiet, as many are. Due to the loss, chairman Mike Ryan and EVP Director of Account Management on Chevrolet Tim Keaton aren't looking so hot. No word on which other agencies were in on the review.

The notification, which came in writing, was delivered yesterday. We hear at least one layoff may follow; SVP/Planning Director Tom Down — former CEO Peter Dow's son. It's rumored that his weight was not being adequately pulled.

XM's spokesperson said the review has nothing to do with the recent XM/Sirius Radio merger. Funny thing is, we never asked if it did. Regardless, it seems GM/OnStar is unhappy with the creativity (or lack thereof). We hear Chevy may be reorganizing from the top down, as well.

In fact, the creative, account and planning leads on Chevy are reportedly supposed to meet with CE's CCO Bill Ludwig on the subject. But we aren't sure when that's going down. Potentially, Mike Ryan could become the active lead on Chevy, and Tim Keaton likewise would head to the business planning position. Note the tongue in cheek, as this information has yet to be confirmed.

We're working on getting our hands on the memo that went around on this subject. It was literally printed out; we assume so no one could e-mail it to us. Haven't those CE folks ever heard of camera phones? If you've got a copy, whip out that Crackberry or iPhone and e-mail us at agencyspy at gmail dot com.

Campbell Ewald did not immediately return our phone call, probably because the office was closed. We work later than they do? No way!