Looking at a lot of different geek forums, I have been surprised that this seems to be one of the most popular sentiments about the DC relaunches: "I am so excited about this. I am reading marvel, but now I can read some DC without worrying about lots of old continuity."
This reaction makes me wonder if these people made sure to read all the Spider-Man, Fantastic Four, and Avengers from the 60's to the present before reading any new marvel.
Of course there are titles like Sandman or Y the Last Man. Stuff with a beginning, middle and end. But in superhero comics there is no end, and "beginnings" seem to happen every 10-15 years. Even as a kid I knew this. I never went up to the cashier and asked how could I read detective comics #487 without reading the four hundred and eighty six before it.
A lot of these characters have existed over 75 years. Sure, you can get the archives and check out the art form in it's infancy. But you need know nothing to dive into a mainstream supers tale!
Don't Be That Guy.