I'm in complete agreement with both of you on this. I know that my first is the same as an Oxford first, because all my tutors told me it was (some of whom had just come from teaching in Oxford). I was an English student, so obviously there would be no disparity between standards of exam questions and such, but it's good to know this is also the case in Law. The fact is that if our firsts were not marked to the same standard as theirs, we would never have got onto their postgrad courses. And Laura, re your job: I got a really sought after job in publishing in London, based on my Hull first and my experience of reviewing for newspapers, before I'd even gone to Oxford (this is a job for which hundreds of Oxbridge grads apply). I think that says it all. Well done on yours!
Bigmouth strikes again, what subject do you do? I got into Oxford based on my marks, which (I admit) were freakishly high, and I got some pretty good references too. It's down to what your subject is and what's required of you. I was lucky in that one of my tutors at Hull encouraged me to write for the Guardian and things, so this would have gone hugely in my favour in an Oxford application. But you don't have to have done that. Oxford has no snobbery towards Hull that I have detected, so as long as you get a first (and, depending on how competitive the course you're applying for is, a high 2:1 might do), you'll have a good shot of being accepted.