Big swings in the market means you'll need impeccable timing when considering a lock. My guess is tomorrow we may see a bit of a reversal in both stocks and bonds- a normal event given conditions as they are. The trend is definitely a borrowers friend at this point.
2.75 5/1 is pretty much the norm at this point - sourced from both brick and mortar and internet bankers. For the risk tolerant there's always financing on a 3/1, which are approaching the 2.25% range for a zero cost refi. (55% LTV, 781 FICO, etc) Bear in mind most 5's and 3's have some pretty stringent qualifying guidelines given how soon the first adjustment is coming.
My .02c
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