Just a quick link out to ICv2's Steve Bennett, whose column Confessions of a Comic Book Guy--Does The Name Slappy Freelance Ring A Bell? continues to make the case for trades that I've been harping on for a while now. Of course, as I'm not a comics retailer, it is all rather murky and hypothosis based, so its nice to read that its working for someone!
To whit - the trade is simply a better format to induce adults to actually pick the damn things up... whether Maus, Watchmen, Persepolis, The Salon or 300. If it reads like a book, and looks like a book, its a book, not a pamphlet.