that would depend on the amount and the way it is presented.
now, this is kind of like banners all over the web. I don't really mind the Google AdSense banners; they're text-only and often (no, not always) related to the page I'm browsing, and sometimes I even click one of those banners because it links to something I *might* find intresting.
But unfortunately there are idiots who put flash banners with fancy animations (let alone SOUND) on their site... and *that* is annoying.
therefor, if I'd maybe get one or two 'spam' messages in the week about something I slightly care about, it would be a lot less annoying.
I doubt spam will ever evolve that way, though.