Immediately after the update was announced this morning, owners of HTC devices (8X and 8S) started complaining that the update was not available for them, while many were proudly boasting their own upgrades over social media.
Per an update to the Windows Phone Preview for Developers Information and FAQs…
There are a small set of devices for which we aren’t offering the latest build of the Developer Preview program due to an identified problem that requires mobile operator or OEM driver updates. These will be offered when the official update for your phone is available.
While the note doesn't explicitly cite HTC devices as those not in line to receive the update, it does seem to answer the questions raised this morning. We'll have to watch and wait patiently to see if HTC rolls out driver updates so those who have chosen to run the Developer bits can gain access.
This may highlight a potential problem for Microsoft. If now owning the Lumia brand means that those choosing non-Microsoft hardware have to wait longer for updates, why would anyone really choose non-Microsoft devices? If Microsoft isn't careful, a couple things might happen. First, anticompetitive practices could be raised. Secondly, Microsoft has worked hard for the past several months to assure handset manufacturers that they actually do want partners to help proliferate their mobile OS. Many hardware manufacturers cancelled entire Windows Phone lines, but have since shown renewed interest.
I know it seems a bit too early in throw a warning flag, and Microsoft's smartphone OS market share is still pretty dismal, but it's definitely something to monitor.