Re: So if I had bought a Windows Phone 8 on day of issue  ...
Skimming through the version history for iOS, it would appear that the support/update cycle for any giver version, i.e. ios3, ios4, ios5, etc. is a little over one year with Apple too. If you bought an iPhone 4 on day of issue, Apple expected you to upgrade the OS to the next version as it was released and didn't continue to support the originally installed version beyond 13 months if you didn't bother to upgrade to iOS 5.
iOS 4, released 21/06/2010, end-of-lifed as iOS 4.3.5 25/07/2011
iOS 5, released 12/10/2011, end-of-lifed as iOS 5.1.1 25/05/2012
iOS 6, released 19/09/2012, probably not long to go now before final update released either
If iPhone users are getting on okay with 'roughly' annual major version upgrades, why is it not going to be okay for WP users? I think this WP update cycle story has spread around the 'net without due consideration and I expect to be reading an official statement from MS on this in the next few days.
If MS don't clear this mess up with a statement, they're idiots and deserve to have consumers thinking that their partners are selling phones with an unsupported, obsolete OS, like the stories try to implicate.