Kathleen Parker, the co-host of "Parker Spitzer [5]," CNN's four-month-old, ratings-challenged primetime show, has been dropped from the program, CNN announced on Friday.  Eliot Spitzer, her co-host, will remain, and beginning on Monday the show will be called "In the Arena."

"We have decided to take the show in a new direction," Ken Jautz, CNN's president, wrote in a memo to staffers Friday. "We will be adopting an ensemble format with several newsmakers, guests and contributors joining Eliot Spitzer each night."

E.D. Hill and Will Cain will join the program, Jautz announced, adding that Parker -- who says she wants to refocus on her syndicated column -- "would continue to appear on CNN occasionally."

The move had been rumored -- both inside and outside of CNN -- for some time now. Spitzer hosted the show solo earlier this month while Parker was reportedly sick, and saw a 68 percent jump in 25-54-year-old viewers [6]. And according to the New York Post [7], Spitzer had been telling friends Parker's exit was imminent.

The 8 p.m. show was announced last fall [8] as a replacement for Campbell Brown, with former CNN president Jon Klein's seal of approval. The roundtable format -- with Spitzer, the former New York State governor and Parker, the conservative columnist -- marked a shift to opinion-based programming for CNN, which had shunned the ideological fare favored by Fox News and MSNBC.

But Klein -- who had long resisted the rising tide of “partisan” news -- was bounced in September [9], with Jautz replacing him shortly before "Parker Spitzer's" October debut.

The new program, Jautz said, will "provide context and analysis through balanced and thoughtful discussions and interviews with a wide range of guests and newsmakers who cumulatively represent various points of view."

The ratings for "Parker Spitzer" simply never materialized. In its first week on the air, "Parker Spitzer," had an average audience of just 465,500 viewers for its debut week; disgraced former CNN host Rick Sanchez's "Rick's List" averaged 468,000 total viewers during its brief run in the same time slot. (It even lagged behind HLN's Nancy Grace, who averaged 550,000 total viewers during the "Parker Spitzer's" first week.)

That "Parker Spitzer" struggled out of the gate was magnified by Piers Morgan's relatively strong debut last month as the primetime replacement for cable legend Larry King.

Morgan's first show drew 2.1 million viewers [10], good enough to increase the news channel's prime-time performance by over 200 percent from its fourth-quarter average, but not good enough to overcome Fox News rival Sean Hannity, who averaged nearly 2.4 million viewers in an interview with Sarah Palin.

According to the newsroom source, there may be more changes on the way. "Parker Spitzer's" lead-in at 7 p.m., "John King, USA," has struggled in the ratings, as well.

Here's the memo from Jautz to CNN's staff, as well as statements from Parker and Spitzer:

I want to share with you some news today regarding our 8pm show. Kathleen Parker has decided to leave the program to focus on her writing, and we have decided to take the show in a new direction. We will be adopting an ensemble format with several newsmakers, guests and contributors joining Eliot Spitzer each night. The new program will be called, "In the Arena," beginning Monday.  E.D. Hill and Will Cain will join the program as well others within and outside the CNN family.

We have been pleased with how the 8pm hour has become a centerpiece of substantive, policy-oriented conversation, and we are looking forward to building on that with this new format. Simply put, the new program will look beyond the headlines to analyze and discuss the most important stories of the day. The program will provide context and analysis through balanced and thoughtful discussions and interviews with a wide range of guests and newsmakers who cumulatively represent various points of view.

Kathleen will continue to appear on CNN occasionally to provide her insights and commentary. We thank Kathleen for her hard work and all that she has done to help us launch our new 8pm program. We respect her as a colleague and appreciate her perspective and contributions.

Statement from Kathleen Parker:

After bringing viewers a new 8pm show on CNN, I have decided to return to a schedule that will allow me to focus more on my syndicated newspaper column and other writings. While I am extremely proud of the show we created, and the subject matter and level of discourse Parker Spitzer promoted every night, it was a difficult decision to scale back my column a few months ago and, with the show going in a new direction, it is a good time to move on. I want to thank the viewers who have been so kind with their comments and support. I will continue to appear to contribute and analyze occasionally on CNN and look forward to continuing my relationship with CNN and the many talented individuals I have worked with here.

Statement from Eliot Spitzer:

I wish Kathleen all the best in continuing on with her spectacular career. It has been a joy working with her as a teammate, and I continue to be a huge fan of the wisdom that jumps from her written work and the wit, charm and insight she brings to all that she does.