Well a few things...
The AT&T network since the iPhone has come out has had a 5000% increase in traffic. Users who are not only using airtime but a ton of data. You take the iPhone and put it on any other network the same thing will happen. The carrier will struggle to keep up with demand. Adding 15 million phones is one thing, adding 15 million phones that are heavy in data usage is another. Don't tell me people with BB's and other smart phones use allot of data, because compared to the typical iPhone user they don't. I do say AT&T needs to do a better job of improving their network but you also have to give them leeway because it takes time to get permits and install towers to carry the increased load.
Now the Droid won't over take the iPhone in terms of market power (which is different from market share) because the platform is fragmented. Yea you can have 100 different models out there. But the problem is that the software development is going to suck, why? Because of a lack of consistency. Each device will have a custom flavor of Android to "suit" their users needs. Each will have slightly different features which will make it hard for consumers to switch from one device to another comfortably because the manufacturer decides that this phone should have this feature while this one should have a different feature. Some of them are touch screen and some are not, etc, etc.
Now where am I going with this? Say you are a developer and you are designing a program to run on the platform. The two most important things for an application are it's UI and functionality. With each different device you can have different sized screens, different orientation, different ways to input data and control the application. So if I'm going to develop an application for the platform and I want it on more than one device I'll have to make modifications to the base code in order to tweak it for each different flavor of android out there and by having to do that it'll take time and effort while developing for the iPhone OS is a one shot deal.
Now you may not like the iPhone for whatever reason, but at the end of the day an iPhone is an iPhone. Look at the history. When the iPod came out no one said it would do well. Then it started to take off and companies kept coming out with their "iPod Killer" none of which even managed to dent the iPod's dominance, the only iPod killer was when Apple released a new model of an iPod. When the iPhone came out Palm, RIM and Nokia were king and now they are all suffering.
Companies should not care about market share, they should care about profitability, the terms are sometimes synonymous but usually not. Look at the computer business Apple has a very small market share than HP, Dell, Leveno, etc but their profit margin dwarfs all of them (in the computer business) and while the Android devices may gain market share their profitability margins will force them to be in second place.