On: Ack is designed as a replacement for 99% of the us...

[mbel]

The name is one letter shorter. Here are some other advantages listed: http://beyondgrep.com/why-ack/

[datalist → mbel]

Thanks, though I hope that statement came with a pinch of sarcasm ;)

The list reads more like a list of features though than "advantages over grep".

[Kurtz79 → datalist]

About the command name length, probably a running joke ?

This is from the feature list of the Silver Searcher, listed above:

"The command name is 33% shorter than ack, and all keys are on the home row!"