How many non-Honeycomb tablets are even sold at stores besides the Galaxy Tab? I have serious doubts that non-Honeycomb tablet sales amount to any meaningful number.
You seem to want to ignore the top two selling Android tablets, I can understand that but to be fair we should ignore the top two selling Apple tablets. That seems reasonable. So Apple has 0% marketshare and Android has about ~90% using those guidelines.
The manufacturers produce and ship units based on their projections.
I work in distribution, maybe in some fans dreams that is how it works. A manufacturer doesn't tell me what they are sending to my warehouse, that isn't how it works. They present a product, and I decide how many units I'm going to buy in. They may produce them in such a manner, but they don't get to randomly ship me what they want, will be a cold day in hell before that is allowed
What happens when sales are way below their projections? Prices get slashed (see Xoom, Iconia, Thrive, Galaxy Tab 7", TouchPad, Playbook).
If we agree that we are going to ignore the iPad 1, the Nook Color, the iPad 2 and the Transformer then the Galaxy Tab actually sells extremely well. If not, then you may want to rethink your stance. The Nook Color had moved roughly 3 million units by the end of March(hitting 600-700K units per month). One model of one tablet had sold a million units more then your entire market estimate
six months ago.
http://venturebeat.com/2011/03/28/nook-color-3m-shipped/
Mac fan sites are pointing to Android's marketshare at this point in the tablet market, I quoted a Mac fan site to start with. Only the most fanatical loyalists to the company are going to argue market data.
The reality is there is a rather decent sized market for Android tablets. Odds are fairly good when Samsung gets these put in the store next to iPads, it's going to make the iPad look cheap by comparison(IPS can't touch the impact of OLED on a showroom floor). What price point they push it at is going to have an impact, but there are a lot of people in the geek community that would love to get their hands on an OLED, ANY OLED, tablet.