I think the WEC was there to promote the bantamweight and featherweight divisions. As they merged into the UFC and Strikeforce's contract was close to it's end, there was no reason for the WEC to stick around. I think Dana plans to replace the WEC with Strikeforce as a secondary organisation.
HW: Alistair "THE DEMOLITION MAN" Overeem - Junior Dos Santos
LHW: Hendo - Lyoto Machida
MW: Michael Bisping - Cung Le
WW: Nick Diaz - Josh Koscheck
LW: Nate Diaz - Gray Maynard
FW: Jose Aldo - Mark Hominick
BW: Miguel Torres - Urijah Faber