Yeah, the Pre-Crisis notion of the multiple Earth was stupid and out lived its usefulness. It was a good move to ditch it.
However, I'm willing to give the re-introduction of it a chance. More to point, I am curious about what they are going to do with it. Will it be the same as before with multiple Supermen and Batmen wandering around? Or will it have its own set of characters? Will it force a World War II connection to a present day JSA? Or will it be a simple parallel world where the JSA was founded in the present day? Or will the whole thing take place during WWII? Or was the JSA active during WWII and they actually
did something about it, giving Earth-2 a whole different history?
There are lots of possibilities and avenues that can be taken with an alternate Earth concept. I'm hoping they will go wild and take risks with it instead of playing it safe and making it more-or-less what the Pre-Crisis Earth-2.