did you ask what the points options are? i paid a little to get a lower rate (obviously that requires you calculating your savings and seeing how long it will take to make back that money and decide if its financially worthwhile)
I'm kinda tight with the up front expenses, So it'll need to be a significant savings for me to it. What did it cost you and how much did it save you?
According to my broker and his pricing, the 3.625 has a lot of "cushion", and tomorrow, it will most likely go down or stay put.