Earlier in the week, Microsoft started shipping "NoDo", the first major update for Windows Phone 7 that brings copy and paste support to the platform, along with some performance improvements and bug fixes. What the company wasn't revealing back then was who would get the update, or when they would get it. The company has previously intimated that carriers can "delay" updates for "testing" (even though this doesn't make much sense), so the rollout was due to be staggered. Unbranded phones (that is, those without network operator logos plastered all over them) in the EU would receive the update first, with carrier-branded phones receiving them at some point in time thereafter.

First the good news: Microsoft has now published a schedule of sorts for the updates. Instead of having to guess or hope that the carrier will disclose its status, there are now lists for the US and for the rest of the world to look at. This is the kind of transparency that the company should probably have been offering since day one—instead of leaving users playing guessing games and wondering whether they were meant to get the update or not—but it's certainly a step in the right direction.

The bad news? Not many people are going to be eligible for the update any time soon. Let's start with the "rest of world" page, as it's not quite so miserable. Apart from a few stragglers, most operators appear to have shipped the February "pre-NoDo" update, and are currently classed as "Scheduling" for NoDo itself. This means that the carrier has completed its own testing and signed off on the update, and is now waiting on Microsoft to push the button, a process that should occur in the next ten days. There may still yet be delays, due to the staggered, phased rollout approach that Microsoft is using, but at least the wheels are in motion.

The US table is less happy. Sprint's new HTC Arrive is the standout; as a CDMA handset it ships with NoDo already, as NoDo is mandatory for CDMA support. T-Mobile US' two handsets, the HTC HD7 and the Dell Venue Pro, are both "scheduling," so should get the update within ten days. But AT&T? Both NoDo and pre-NoDo are stuck in "Testing," for every model the company sells.

The American table is also a little mysteriously constructed. While the "rest-of-world" table is broken down according to country and operator, the US table is split according to country (even though the entire page is applicable to the US and the US alone) and phone model. The mobile operator isn't mentioned at all, which feels like a rather feeble attempt to spare AT&T's blushes.

As an added bonus, as Microsoft's official Windows Phone 7 support Twitter account admitted earlier today, there's no guarantee that the firmware will ever leave the "testing" state. Updates will be cumulative, but if a network operator never signs off on the testing, that cumulative nature counts for nothing, and it means that in practice carriers can indeed block updates forever.

This will, no doubt, make T-Mobile customers even more excited about the impending merger with AT&T.

As for what this testing actually is, well, who knows. It can't be that significant, or else unbranded handsets wouldn't be allowed to use the update on AT&T's network—but they are. One might also be inclined to point out that AT&T was the first iPhone carrier, and updates for that platform were released a month after it was released, along with another update a month later, and a third a couple of weeks later still. The operator was either uninvolved in the iPhone testing process, or at least worked fast enough to ensure a rapid turnaround. Plainly, getting updates out quickly, even on AT&T, is possible. The company has apparently opted not to bother in this case.

Now, AT&T isn't the only carrier to have both updates stuck in testing limbo, but it's the largest. It's also the carrier described before the platform's launch as its "premier carrier." ("Premier" apparently means "worst"—a twist that nobody expected.) But there are several other operators in the same boat, and this sets a troubling precedent for the platform.

At the end of the day, NoDo isn't that important an update; it's some desirable functionality and performance fixes, but nothing critical. What if this update were actually important? What if it contained a fix for a significant security flaw? Would the company continue to hold its users hostage, and does Microsoft have any recourse to actually make things right for the people using the platform? This is no mere hypothetical concern, either: there are security issues with the platform right now that need fixes urgently.

The current update process leaves users dangerously exposed, and Microsoft surely needs a way to expedite upgrades. Does it have one, or can even critical fixes be stuck in testing purgatory forever?

We've asked Microsoft and AT&T for comment, but have not received one so far.