Ares I was to serve as a manned transport to orbit for ISS and eventually support manned lunar missions. Ares V was to be the heavy lift rocket to heft large unmanned payloads for manned lunar missions, etc. They both used different shuttle derived components.
The DIRECT concept skips the Ares I and goes straight to various configurations similar to the Ares V, but man rated.
Both will be expensive and not much more reliable than the shuttle (if even that.)
Basically it comes down to the old NASA pissing contest between JSC and MSFC for who will control the next big program.
My guess is that the Obama crew will put a pox on both houses and divert NASA pork to NASA centers in bluer states like Goddard in MD, Ames and JSC in CA and Glenn in OH.
More likely divert it to his social spending instead. NASA just doesent deliver him enough votes, and Md. and Cal. is in his pocket regardless . (Ames is small beans..)