There is a rather interesting discussion going on over in the forum just now regarding permission.
I don't generally do the type of street photography that requires permission partly because I just don't take pictures of people all that much, partly because if I was to, I'm not the type to be able to walk up to a stranger and speak to them regarding a photo I taken of them.
Over the last couple of days, I've almost actually stopped some people in the street to ask if I can take their photo. It's something I wish I could do. I've now packed a few of my blipcards into my wallet to aid the discussion with potential subjects.
I took a wee trundle up to my local skatepark tonight to find that, Yaaaayyyy, the contractor had been to fix their god awful mistakes with the transitions they did last year. I must say, they seem to have done a no bad job. not flawless, but certainly looks a lot better than the first attempt. Time will tell though.
I actually did ask permission for this picture. Unfortunately, I can't remember his name but the permission in this sort of case is easier because I skate up there all the time and know a lot of the locals or they know me.