Here's my take, and why the Chronicles are now green: I live in a city, Toronto, with a fairly large Iranian population. And if the last few days have shown anything, it's how wired the kids at the heart of this movement are.
So if I wear green for the next however long as I walk around my city, and someone notices and asks me why, there is a chance -- however small -- that word will get back to Iran that "people in Toronto are with you." And if someone stumbles across this blog at random, there is again that small chance of my tiny, insignificant act of solidarity reaching a set of eyes or ears that needs to know they are not alone in this world.
It makes no difference to my life, and it might make a difference in someone else's, even if the odds of it doing so are somewhere south of 1% of 1%. If that makes me narcissistic, so be it.
Of course the real problem is the majority of my wardrobe is along the black/grey/white/blue spectrum... heck, I had to bust out an old Pinky & the Brain t-shirt today (ironically featuring a timely "Your Candidate for World Ruler" slogan) to wear something green.
When I start a 'Shopping for Allah' segment here, then you can accuse me of narcissism.
UPDATE: Glenn Reynolds hops on the green bandwagon. Green the 'net!