Not really understanding the confusion.

by NsU Soldier @, Washington, Tuesday, February 12, 2013, 21:38 (3419 days ago) @ JDQuackers

Yeah, I don't know the exact meaning of the red arrows, but I use them as such:

Purple link, grey arrow == Old and read
Blue link, grey arrow == Yeah, I reddit already and it's old as shit
Purple link, red arrow == A little bit old, but very recently read
Blue link, red arrow == Alert! Alert! Unread post trying to hide!

It's almost certainly this.

Blue = Unread Post
Purple = Read Post

Gray Arrow = Reply
Red Arrow = Recent (New) Reply

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