The following were listed in the Triathlete magazine...basically, you know you are are triathlete when.... (the ones in bold apply to me)

-Your bedtime is that of a preschooler
-Compression garments have made their way into your business attire
-You have no problem disrobing in public
-You have no problem spitting and blowing your nose without a handkerchief
-You are willing to tattoo a business logo onto your skin, permanently
-You know the weight of each bolt on your bike but can’t find the oil-measuring stick thingy foryour car
-You come back to work after vacation exhausted and needing more time off
-Laundry day is when you run out of workout clothes
-You plan your wedding for the winter to accommodate your race schedule and those of your guests
-You smell permanently of chlorine and your hair is tinged ever-so-slightly green
-You check youre e-mail/Twitter/Facebook account while wearing your cycling kit and a helmet
-Your breakfast, lunch and dinner consist of Clif/Power/Name-your-brand bars, all consumed while moving at a fast speed
-It only takes one beer and your quads go tingly
-Spandex isn’t tight enough
-Your bike on the roof rack doubles the price of your car
-You can use the word “fartlek” in a sentence without giggling
-You wear a wetsuit in the pool
-You sleep with a heart rate monitor on
-You have downloaded Powertap files while at a dinner party
-You’re either swimming, biking or running in your Facebook profile picture (sometimes!)
-You have no idea when your friend’s birthday is, but you can list her run splits from the last three races

i guess i have a ways to go until i'm actually a triathlete! no tattoo for me though!