But a week after Couric's debut, that's probably not going to happen. On her first night, Couric shot up to No. 1 in the ratings, and while she finished out her week still at No. 1, her ratings have been slipping.

Media planners and buyers, having watched Couric over her first several days, remained convinced that her slide will continue, according to a Media Life poll. This conclusion is consistent with a reader survey back in the spring, when Couric's appointment was first announced. Back then they believe she would see a brief bump but would soon settle in at No. 3.

Media Life asked readers: After seeing Couric’s opening-week ratings, where do you think she’ll rank among the three newscasts six months from now?

Just 19.5 percent believe she will remain in first place. The largest share, 40.7 percent, think she will sink to No. 2. But almost as many, 39.8 percent, believe she will sink to third place.

Readers did not believe Couric's ratings burst would last very long, with 57 precent giving it just another week. About another third of respondents, 32.5 percent, gave it another month. Only 10.5 percent thought it would last indefinitely.

Readers also believe that NBC, which appeared most hurt by Couric's debut, will bounce back after slipping to No. 3 last Wednesday.

Almost three quarters, 73.7 percent, agreed that the dip was the result of former "Today" fans switching over from the NBC evening broadcast to sample Couric but that they would return to watching Brian Williams. The remainder felt those viewers would stick with Couric.

Readers were divided over Couric's performance in those first several days. Media Life asked: Now, having seen her newscast, are you more or less optimistic about her long-term abilities as “Evening News” anchor?

The largest share, 36.9 percent were less optimistic, agreeing with the statement: "Her broadcast is nothing but fluff. She seems nervous and I’m baffled by the story selection. CBS would be wise to move her to 'The Early Show' and quickly."

But 27 percent were more impressed, agreeing with the statment: "The newscast isn’t perfect but it is different, and I’m encouraged by CBS’s willingness to take chances. I think she’ll find her groove and stay at No. 1 for a long time."

The remaining 36 percent were undecided.

In any case, readers do not expect that ABC and NBC will revamp their newscasts to the softer format introduced by CBS with Couric's debut.

Media Life asked: Will the new CBS format force ABC and NBC to add a more newsmagazine-ish feel to their broadcasts? 

A sizeable majority, 83.2 percent, think not, agreeing with the statement: "As soon as Couric’s viewership fades, so will any talk of imitating her."

The remainder agreed with the statement: "Yes. I predict that ABC and NBC will steal many of the features of Couric’s new broadcast, such as the nightly opinion pieces, snapshots and focus on softer news."