First, lets note that Roy Williams has only 1 year with more than 850 yards, and only 1 year with more than 64 catches. Both of those feats came during the 1 year he had passing guru Mike Martz as his offensive coordinator.
This year, he's been pouting and dropping easy passes, so lets not call him a high character/lead by example type of guy.
For that production, the Cowboys gave-up their 2009 first-round, third-round and sixth-round picks, plus a seventh-round pick in 2010.
Then there's the contract via PFT:
Per Chris Mortensen of ESPN, Williams’ five-year extension with his new team is worth $45 million. The contract also includes $20 million in guaranteed money.
But while the Cowboys were careful not to pay Williams more per year than T.O., Williams still got a better contract, with $7 million more in guaranteed money and a longer overall term.
Um, I think we'll spend that 9 million a year (never-mind all of those draft picks) on players who have earned it, thank you.