<edited>
anyway i asked the lady handling my case again. she checked it out and told me, yes its together with the imac warranty under applecare.
as for whether if i buy later than the imac, i dont know liao.like june2013 buy and is it on a mar2013 (imac) warranty or june2013 warranty.
buy imac pls buy applecare. wont regret one if u have any issues with yr mac. even mouse/keyboard etc also covered
(More information on SuperDrive?)
3.2 Covered Equipment
In addition to the Apple-branded product and accessories contained in the original
packaging, “Covered Equipment” includes the following according to your Plan:
(i) Under APP for Mac, (a) one compatible Apple branded display if purchased at the
same time as the Covered Equipment, (b) an Apple-branded mouse, Magic Trackpad,
Apple Battery Charger and keyboard if included with the Covered Equipment (or
purchased with a Mac mini), or (c) an AirPort Extreme Card, an AirPort Express or AirPort
Extreme Base Station, Time Capsule, an Apple-branded DVI to ADC display adapter,
Apple RAM modules and MacBook Air SuperDrive if used with the Covered Equipment and
originally purchased by you no earlier than two years before the Covered Equipment
purchase.
(ii) Under APP for Apple TV, an AirPort Extreme Card, an AirPort Express or AirPort
Extreme Base Station and Time Capsule if used with the Covered Equipment and
originally purchased by you no earlier than two years before the Covered Equipment
purchase.
http://images.apple.com/legal/applecare/docs/081811_APP_English_NA_v5.4.pdf