Agreed on the LoD, how cool would that be? As cheesy as some of those cartoons can look these days, I loved the old Challenge of the Superfriends when I was a kid. I really hope that DC/WB doesn't rush this just to keep up with Marvel. Honestly, I've always been more of a Marvel guy, with my main exposure to DC as a kid being Batman comics and the Superfriends cartoon, but as an adult I have gotten into the DC stuff more as well. I think, at least for the most part, the way Marvel has set up their movie universe is almost perfect. The anticipation and building towards Avengers was great, and Avengers itself was a perfect payoff. There isn't any reason that DC (and Warners) can't do the same with the JLA, and they even have access to their entire library of characters (unlike Marvel with the Spidey/X-Men/FF deals). It seems like they saw how successful Avengers was, and now they are rushing to get to Justice League to keep up (and make money of course).
That isn't to say it still can't be a good movie though, even without the buildup. Obviously, this is the way they are going about it, so I'm still going to hope for the best. I was just reading an article the other day about this (when the Darkseid rumors hit) and they really need to put their best foot forward with this. They are going to have a lot of competition in the summer of '15 (just Star Wars and Avengers alone), and if it bombs or gets buried that could really hurt the chances of any non-Batman characters/movies in the future. I hope they get their stuff together. Heck, Marvel has me excited for a Guardians of the Galaxy movie - a team I really didn't know about prior to a few years ago - and that's from someone who has been reading Marvel in various capacities since I was 5.