Personally, I think both sides got a good deal out of this trade. Williams is a 1st round talent, who already bypassed the growing pains of a typical WR's first few years in the NFL. Plus, the Cowboys had two 3rd round picks this year, so they still had another pick in that round to fall back on.
Think about it. WR's don't usually come into the league and contribute right away as a rookie. Roy Williams is a proven play maker and is only 26 years old. Terrell Owens is 34. Jerry Jones wants to ensure that his team is exciting and competitive now and in the near future when they move into their new state-of-the-art stadium.
With that said, there is absolutely no reason why this offense can't overcome their playoff woes now. If all these offensive weapons stay healthy, there should be no excuse. On paper anyways, this has to be one of the scariest offenses EVER assembled!....
QB: Tony Romo
RB: Marion Barber
RB: Felix Jones
WR: Terrell Owens
WR: Roy Williams
TE: Jason Witten