You can see that the AT&T's phones, the Surround, Quantum, and Focus, are still in the testing phase. Internationally, Spain's Telefonica still has their phones in testing and most of Deutsche Telekom is also in testing. Testing can last an indeterminate about of time. Once testing is done, the update is "scheduled" and that can take 10 days. Then delivery begins, which is where the vast majority of carriers are.
For those still in the testing phase, it is tempting to take shortcuts to get the NoDo update. The Unwired blog has detailed info about a tool called ChevronWP7.Updater that will bypass the waiting and pull down the update for your phone. You can read the article, but don't bother trying to get the tool. If you have it, you might want to think twice about using it. According to the author, Microsoft has contacted him and pointed out a few issues with the tool that may prevent your phone from receiving any future updates. That would be bad since Mango is due later this year and will have Internet Explorer 9 built in.
Microsoft itself wrote about the issue on the Windows Phone Blog.
"But my strong advice is: wait. If you attempt one of these workarounds, we can't say for sure what might happen to your phone because we haven't fully tested these homebrew techniques. You might not be getting the important device-specific software we would typically deliver in the official update. Or your phone might get misconfigured and not receive future updates."
It is a shame users are in the position of wanting the update so bad and were under the impression this fragmented release cycle was a thing of the past for Windows Phone. When Apple releases an update, it is there simultaneously global for just about everyone. It is noteworthy though that Verizon iPhone owners are still on 4.2.6 of iOS whereas the rest of the world has moved on to 4.3.1. Thankfully, this update is a small collection of patches that no one was chomping at the bit to receive.
On the other end of the spectrum is Android where updates for devices can be separated by months or worse, your phone may not get an update at all from the manufacturer or carrier.
Microsoft was supposed to be somewhere in the middle, far closer to the Apple end of the spectrum than the Google end, but if you ask some users, it is looking more like Google's rollouts.
Hopefully, Microsoft and the carriers are learning from this experience and will take corrective action before Mango or any other updates show up. Even if they do though, everyone that is until in testing mode has received a black eye from this experience. That isn't good for the new kid on the block. He should be showing everyone else up to show he is worthy of comparison.