They've been selling the 3GS continuously since summer 2009. Of course they're still making new ones. Tim Cook wouldn't have his current job if in his old job he'd accidentally booked years of surplus units.

See also Anandtech's writeup of the substantial new chip fabrication improvements going into this year's version of last year's iPad: http://www.anandtech.com/show/5789/the-ipad-24-review-32nm-a...