new string-formatting preferred? (was "What is this syntax ?")

[Tim Chase]

On 06/20/2011 05:19 PM, Ben Finney wrote:
> “This method of string formatting is the new standard in
> Python 3.0, and should be preferred to the % formatting
> described in String Formatting Operations in new code.”
>
> <URL:http://docs.python.org/library/stdtypes.html#str.format>

Is there a good link to a thread-archive on when/why/how 
.format(...) became "preferred to the % formatting"?  I haven't 
seen any great wins of the new formatting over the classic style. 
  Is there some great feature of new-style formatting that I've 
missed out on that obviates bajillions of lines of 2.x code?

-tkc