It's more selective, it just replaces things like "rofl", "teh" or "lulz" with more intelligent and/or amusing alternatives.

( The Mock TurtIe ™ --- Thinks you are a cunt, on, Mon 1 Jun 2009, 0:20, archived)

Worthwhile.
l u l z
( Dave Trouser ; the people's choice - 75% agree, Mon 1 Jun 2009, 0:23, archived)

Indeed.
www2.b3ta.com/host/creative/37452/1243812617/filter.jpg
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Mon 1 Jun 2009, 0:31, archived)

Excellent.
You have become Robin Johnson, only worse.
( Dave Trouser ; the people's choice - 75% agree, Mon 1 Jun 2009, 0:33, archived)

Next you'll write one to correct common typos and grammatical errors.
A sad day indeed.
( Dave Trouser ; the people's choice - 75% agree, Mon 1 Jun 2009, 0:34, archived)

ps
IuIz
( Dave Trouser ; the people's choice - 75% agree, Mon 1 Jun 2009, 0:36, archived)

remember to use textcontext instead of innerHTML
lol

and make sure it's not case sensitive RofL
( Gilgamesh gazed in wonder as Frampton came alive, Mon 1 Jun 2009, 0:36, archived)

[picard ascii]

( Dave Trouser ; the people's choice - 75% agree, Mon 1 Jun 2009, 0:38, archived)