Meet the new booster, same as the old booster. Looks like they ganked the already-proven Ares first stage and are planning to mate it with a slightly modified Ariane V upper. The J2X program was turning into a classic NASA "let's take a good idea and ignore all the cost savings and do something cool with it" over-reach, so the substitution makes sense. That said, from what I've read that wasn't where the cost overruns were coming from. Also, there's no mention at all about what sort of capsule might be used. Wouldn't it be interesting if SpaceX capsules would fit?