econjack:
I often use:LiquidCrystal lcd(12, 11, 9, 8, 7, 6); // Setup the LCD hardware interface pinsfor my LCD's. The reason is because the UNO uses 0 and 1 for the Serial object (as Bob pointed out) and pins 2 and 3 are used for external interrupt service routines. If you don't ISR's, pins 2 and 3 are usable, too.
I often use:
LiquidCrystal lcd(8, 9, 4, 5, 6, 7); // display pins
This cabling keeps free many useful pins like:
pin-0/1 used for Serial debugging
pin-2/3 which can be used for hardware interrupts
pin-10/11/12/13 which are the SPI pins on Atmega328 boards
pin-A4/A5 which are the I2C pins on Atmega328 boards
Of course, LCD cabling could use other pins, including the analog pins A0, A1, A2, ...