The only time I'll buy something used if its in the 3-6 year old range, when its not old enough for people who horded copies to really be selling them yet and when its just old enough that there's no new ones being delivered to stores. I had to do that with a few of my games, namely Mirror's edge and Metal Gear Solid 4.
By the same token though, I wont buy it digitally, even if that counts as a new copy effectively, because I don't like not having a physical proof of purchase should something happen to my account.
E3 is going to be very interesting this year I think. From the consoles but also to the games that have been announced, games yet to be announced and more.
Personally I'm hoping for news of The Last Guardian. I couldn't stand Ico or Shadow of the Collossus, but just the nature of Trico, along with the developments of AI and the sheer amount of 'escort' games coming out lately and the design of them (Bioshock Infinite, The Last of Us, etc) and how that has moved along so much from say Resident Evil 4.