Anyway about it, we are right on the aspect where 8.1 is feature locked, no question, final on that aspect. Any new features (Xbox, file manager, etc) will come via a App, and personally, I like this model due to not having to wait for a GDR for a OS based feature update. I really do welcome this.
With that being said, I still feel this thread is almost a fail. As quoted from Joe, the Dev prievew is not final in the aspect of bug fixes but, IS as features go. So it is not the final. The name of the thread "Windows Phone 8.1 DP IS Final/RTM OS. Period." I dont think "Period" is really right here. If the bug fixes come down before it's sent to the phones from the carrier (not including firmware upate and that will be mostly carrier and carrier compatablity issues), then it's not the final... PERIOD.
This thread would be partly right...Final as features go sure but, not cut and dry like you make it out to be.
We're not talking about semantic.
We're talking about Build numbers and development process: DP is RTM.
RTM means that OS is finished, and sent to manufacturers to be pre-installed on millions of devices. It's the same exact version.
Every bugfixes, drivers/firmware updates, new features, any changes of any kind will come AFTER and ON TOP of the RTM build, that will remain the "Final" (yes, final) OS base from which further improve the product.
That will happen:
1) Through Windows Updates (OEM/Official channel), Microsoft GA patches + Firmware (Cyan) included before launch;
2) Through Windows Store (Updated Apps, ready for launch);
3) Backend Updates (Microsoft Servers -> see final Bing/Cortana before launch).
It doesn't matter though -> DP will remain the base OS for all those fixes, for every OEM and Dev.
Exactly like Windows 8 and 8.1 RTM were even before GA patches, Apps updates and so on.
Joe said DP is NOT FINAL to simplify things to everyone (it should had used "Not the Full Package"), but that's not correct:
OS is Final, it only misses maintenance patches and updates that OBVIOUSLY will arrive for everyone before and after launch.
But that's very different from calling it "Beta" or similar.
In fact if you installed DP, you have the latest Stable Channel version of it, and you're good to go to further (obvious) updating without the need to reinstall things, Reset devices again, and so on.
You have the final version of Windows Phone 8.1, before any other else, before even Drivers manufacturers in some cases.
You have only one portion of the Release update, but that portion is a finished product.
Just hold on for further fixes and optimization that will come as soon as they're ready.
That's all about it.