Arena rap would be songs like 'Love The Way You Lie', which I am unsure is the first of it's kind, given songs like 'Love Your Life' preceded it, as well as 'Empire State Of Mind', and 'Can't Tell Me Nothing'. I think some of those songs are dope, but my thinking is that they became more and more calculated and designed to attract a certain kind of crowd. 'Love The Way You Lie' may have pushed that style forward.
I never really fukked with Eminem, this album wasn't great by any means, but I found a few songs listenable, esp. that summer, I had a 'financial setback', and I remember finding a minor kind of solidarity in the kind of odds overwhelming production style.