If you are luck enough to drop enough tiles that you cover two “triples,” do you count that as 6 times the letter scores or 9 times?
(Yes, I know that that spans 8 spots, and at least one letter has to already be on the board.)
Nine times.
If you’re looking for some high scores in scrabble, you should know these words.
http://members.aol.com/gulfhigh2/words14.html
Jacques Kilchoer
Workers of the world, unite! You have nothing to lose but your chains.
Don’t forget to add 50 for the bingo!
Nine times says WHO?
Nick - You do get 50 points for a bingo, but you can play a triple-triple without playing a bingo.
Yes, it is tripled and that score is tripled, which means it is effectively x9.
Now then - Play a 15 letter word on three Triple Word Scores and you get 3x3x3, or 27 times your score!
I know my Scrabble, kids… Not much else, unfortunately…
Yer pal,
Satan
Not to beat a dead horse, or anything, but who SAYS you get to triple the already tripled score? Can someone quote the rule that governs this, please? 
From Official Scrabble Tournament Rules
found online at www.math.utoronto.ca/~jjchew/scrabble/rules/nsa.html
I will concede that Official Tournament Rules occassionally differ from the rules in the game.
That said, the Triple-Triple rule is the same in the rules that come with the game. Direct from the Hasbro site at www.hasbroscrabble.com/rules3.html is the following: