According to Jon Anik on MMA Live at the 26 min mark:
“Matt Brown has since been cut by the Ultimate Fighter Championship.”
[UPDATE] via Ariel Helwani on Twitter:
Matt Brown has NOT been released from the UFC. This comes from the UFC.
Matt “The Immortal” Brown (11-10)
Loss Brian Foster – Submission (Guillotine Choke) UFC 123
Loss Chris Lytle – Submission (Straight Armbar) UFC 116
Loss Ricardo Almeida – Submission (Rear-Naked Choke) UFC 111