MKM Partners analyst Tero Kuittinen told The Street yesterday that AT&T ditched its plans to carry a Motorola Android phone, referring to the HTC Heron which Motorola originally designed to be a Windows Mobile phone, and then reportedly retracted at the last minute to load up with Android instead.

A lot of pundits have put a lot of weight behind Motorola’s first two Android handsets, saying that this is the company’s “last chance” to recover its phone-producing arm, or some sort of swan song because of the spin-off that was supposed to take place in the third quarter of 2009.

Last October, Co-CEO Sanjay Jha said “While our strategic intent to separate the company remains intact, we are no longer targeting the third quarter of 2009, primarily due to the macro-economic environment, stresses in the financial markets and the changes underway in Mobile Devices.”

Not having support from AT&T is a big detriment, some say, as it’s the only carrier consistently stealing subscribers away from other carriers.

But wait, AT&T didn’t just cock-block Motorola. It’s actually given the big thumbs down to TWO companies offering an Android device. Apparently it pitched HTC’s Lancaster into the dumpster this summer as well, only that time, we don’t know exactly why. Rumors were that it could have been too underpowered or perhaps even too problematic for a successful launch.

Because AT&T is the exclusive iPhone carrier, people often forget that it offers any other smartphones. Maybe they don’t consider any other products noteworthy, I don’t know. But the point is, AT&T’s selection of smartphones is led by Windows Mobile. Check this out:

AT&T's smartphone roster by OS

If you look at these stats as a direct reflection of the U.S. smartphone market as a whole, you’ll notice right away that the OS distribution is kind of out of whack. Yes, AT&T has 70 million subscribers, and that’s an important factor in the availability of an OS…but how much does it really determine market position?

I mean, does Windows Mobile have the lion’s share of the domestic smartphone market because it is the most common OS in AT&T’s smartphones? Of course not: Blackberry does, then iPhone, THEN Windows Mobile.

Let’s assume that on September 10th, T-Mobile and Verizon get Motorola Android phones, and lets see how their charts look.

Here are our friends over at T-Mobile. We know those zany Germans love Android (they got the Samsung Galaxy before anyone else, after all.) However, we see that Android happens to be T-Mobile’s ONLY smartphone OS that isn’t Windows Mobile or Blackberry. It’s probably because they’re too busy gunking up their phone lineup with those silly Sidekicks.

T-Mobile's smartphone OS distribution

And here’s Verizon. As you can see, they’re the most balanced/least diverse smartphone carrier in our list thus far.

Verizon's Smartphones if they get Motorola Sholes

AT&T already offers the most diverse selection of Smartphones, at least by operating system…so maybe it’s not trying to thin the proverbial broth by adding any old mediocre Android device to the pool.

Now, you’re probably going to say “Hold up a second, fancy pants! Where’s the Palm Centro in all this?”

I know right? Check Sprint, they’re the only carrier still offering Palm’s (awesome) gear as of this very moment. While we’re looking at them, you’ll notice that Sprint’s got quite a diverse OS lineup…but that diversity is mostly due to Palm’s multi-platform delivery.

No Android here...yet.

So yes…my point. The carriers we expect to have Android on them also happen to be the ones with the least diverse smartphone selection.

I know there’s only a correlative link between number of OSes and likelihood of new OS adoption (and not a causal one,) so don’t bite my face off for pointing it out.