If this blog was a magic 8 ball, it would say "Outlook not so good" for the Chiefs. From the Star-Tribune's excellent Vikings' blog:
Allen is going to want a lot of Zygi Wilf’s money. Safe to say, the NFL’s sack leader from 2007 is going to want more than the Colts gave end Dwight Freeney last July. Freeney’s six-year contract – $72 million over six years with a $30 million signing bonus — made him the highest-paid defensive player in NFL history.
Considering the fact a player with Allen’s ability could make this one of the top defenses in the NFL, the guess is that Wilf and Co. will pay the price.