JV, rates did go down based on todays move. Not all of todays gains in the MBS market are reflected on ratesheets though. Many are hoping that more of the gains will be passed along tomorrow. However, there is always a risk that we lose some of todays gains during the trading session tomorrow.
Don't focus solely on treasuries. Mortgage rates are determined in the mortgage backed security market. Sometimes they move in tandem with treasuries and other times they can be quite disconnected. Read the MBS Commentary blog for a better understanding on a daily basis.
No matter which way you slice it, today was a GREAT day in the mortgage backed security market.