Unfortunately, none of us can accurately predict where the market will go at this point. Industry analysts are split, and anyone who gives you a definitive recommendation is misleading you. Keep in mind that in the mid-80's rates were in the 12-15% range, a rate of 6% or below now on a 30-yr. fixed is still not too bad, all things considered. Still, 4.75% would have been better so I understand your concerns.
I hope you make the best decision for your family, and good luck!
E Mortgage Management
800.793.9633 ext. 156