Quoting:
:oI was actually terrified of the 60's NBC Peacock as a young kid,as I got older I became fascinated with the animation process and learned to like the beautiful(in my opinion)mascot of NBC. Did anyone notice that as color TV evolved,the Peacock did too(color-wise)?The idea was produced by the NBC Art Department,and le Peacock was animated by Electra Film Labs. There were 2 different musical scores-a full orchestra score for the '50's bird,and later,a simpler score for the 60's Laramie Peacock,performed by the Metropolitan Jazz Quartet!The Laramie Peacock also introduced the colorful'kaleidoscope'background before the animation morphed into the full Peacock plumage.Who did the voice-overs for the Peacock?Please post the name or names if you know! ;)
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Well, NBC has had several logos over the years.  The most memorable are the Peacock, the Snake, the Chimes, and the N.

The chimes is one of the oldest ones.  It was of 3 chimes, and represented the 3 notes (bong-bing-bong) that NBC radio used to announce their shows.

The Peacock came in during the 1960's, when NBC went to "Living Color".  There were several announcers during this time period, depending on when and where you were.  The most famous 2 were Ben Grauer and Mel Brandt.

In 1974 or 1975, the logo became the famous "Snake" design.  It was the letters NBC, that kind of looked like a number 4.  This was I think inspired by KNBC and WNBC, the east and west coast flagships, both were on VHF 4.  It kind of looked like this:

NB
C

This was in some ways similar to a logo that PBS used at the same time, with the animation of the letters comming out, one after the other.

I think it was around 1979 that the "N" logo appeared.  This was a stylized letter N, it looked like a rectangle that was bisected at an angle, and offset.  If memory serves, the top part was red and the bottom part was blue.

In 1986, NBC phased out the N, and placed a newer peacock on top of it.  THis lasted for about a year, until they dumped the N and went with the new peacock.

In 1997, they premiered a new Peacock during that year's live telecast of "E.R."  This is pretty much the same one they use now, with only slight modifications.

I hope this helps clear up your questions.  :)