The 'Hello World' example associated with the LiquidCrystal Library in the Playground has been corrupted and should be fixed up by someone who knows what they are doing (which would not include me). Here's a link to the page I am refering to: http://arduino.cc/en/Tutorial/LiquidCrystal
There are two major problems:
(1) Somewhere along the line the correct example code has been replaced by a copy of the example from SetCursor.
(2) The setup() functions starts with "lcd.begin(numRows, numCols);" which does not agree with the reference information which shows: "lcd.begin(cols, rows) ".
The examples still work because currently (as best I can tell) LiquidCrystal.cpp does not use 'cols' and only checks to see if 'rows' > 1.
Incidently all of the other examples that use lcd.begin implement it correctly with "lcd.begin(16, 2);". It's only 'SetCursor' and this messed up 'Hello World' that are backwards.