graf actually predates hip hop by quite some distance and being into hip hop really isn't a prerequisite, as it obviously is with breakdancing - what else would you dance to?
that's not to say that they aren't bound together in many ways, though. for instance, kodwo eshun writes fabulously in more brilliant than the sun on the way wildstyle graf and his theories of breakbeat science mirror on another.
so, i guess what i'm saying is that undoubtedly graf is very strongly linked to hip hop culture and vice versa, but both could feasibly exist without the other (i bet the graf would look a lot different if hip hop never happened and that it would be a really shadowy subculture that *none* of us knew about, though), whereas other facets of hip hop culture just couldn't.
as ambrose and luka have both pointed out, in the uk, at least, graf has to a certain extent become a preserve of middle-class white boys from the provinces (and one of the country's leading painters is actually a metal fan who's not much into hip-hop at all, incidentally!) but that in no way invaildates it as "street" art at all.
you can be from a relatively privileged background and still be down; just don't front like you're from the wilds of harlesden when you're really from pinner and you'll be okay! this may be me talking from a slightly self- interested standpoint here ("what the fuck is someone who went to boarding school always prattling on about street music and ragga for?!") but there are quite a few of us like that here, me included. therefore someone loving graf and being an old etonian aren't mutually exclusive in my book.
re chantelle's point about dancehall moves cropping up at grime nights: this i really don't find surprising at all. it's totally obvious, what with the way it used to happen at jungle nights and 2step things there's always been a bit of it going on anyway, then figure in the areas where the music is coming from etc. maybe it's just happening a lot more now, though. i dunno. i've not been out in a while... what moves were they doing, incidentally? quite intrigued to find out to what tracks, too. dancehall dances are still a bit of a grey area for me: i have enough of a job keeping up with the music and have two (clubbed) left feet.