Well, it appears that, much like the shuttle, NASA’s Ares rockets are proving difficult to develop.

Originally intended to rely heavily on existing equipment, largely based on the Shuttle, nothing is going that way:

Beyond the much publicised CLV solid-rocket motor oscillation problem, other issues for Ares I include pocket buckling in its upper-stage liquid hydrogen (LH2) tank, an immature first-stage forward skirt avionics box design, protection for parachutes against the interstage’s shaped linear charge separation system and first-stage thrust vector control (TVC) changes.

I expect this to be both behind schedule and over budget, again.