Merriam-Webster's #1 Word of the Year for 2006:

1. truthiness (noun)

1 : "truth that comes from the gut, not books" (Stephen Colbert, Comedy Central's "The Colbert Report," October 2005)
2 : "the quality of preferring concepts or facts one wishes to be true, rather than concepts or facts known to be true" (American Dialect Society, January 2006)

I never thought of it, but it is indeed a remarkable word. It is very useful to describe every heated debate where people are really passionate about one point and argue with the facts that support their theory, and ignoring others. I think this can be applied to almost all political debates, with the way they twist the facts to make their point. I think this is the main reason people become cynical of the politics and government, because of the truthiness they use.

But it is not only political debates, but all passionate topics, just to mention a few from a technology point of view are the usual debates of Windows Vs. Mac OS X, PS3 vs. Xbox 360 etc etc. I have decided to try not to go anymore into my truthiness arguments and just accept that I always like to support the underdog in any battle. Just because I feel compassion or empathy.
Anyways, coming back to the news about the word of the year, this is what Colbert replied:

"Though I'm no fan of reference books and their fact-based agendas, I am a fan of anyone who chooses to honor me," he said in an e-mail to The Associated Press.
another funny quote was the signature of a slashdot user:
You want truthiness? You can't handle the truthiness.