Interest rates (as in mortgage rates) have already started to rise. Unless going for a tracker or variable rate mortgage, the BoE base rate doesn't really make any difference. I fixed my mortgage in January for 5 years and from starting my application to completeing it, the same building society had upped their rates, as have all the others. I can't get the deal now that I got then and that has changed in the just 8 months.
Personally, my wife's just given birth, I already have a 12 year old, so knowing the exact amount I have to pay for the next 5 years was the most important thing for us. Yes I could pay less on a variable rate if the rates go down but I could also pay more if they go up and that could really screw us over. Also, all being well, in 5 years time we will have a more favourable LTV, which means you're less of a risk, so they give you a better rate and cheaper payments, which is counter intuitive really, but that's the way it goes.
I started work for a building society when I was 17 and the interest rate then was 15.4% ! Man that would screw most people over these days.