One manufacturer you can make that estimate for is ASUS. NPD claims that they sold ~120k tablets in the US through October. At around the same time (right arou

One manufacturer you can make that estimate for is ASUS. NPD claims that they sold ~120k tablets in the US through October. At around the same time (right around the Transformer Prime launch, I believe), ASUS claims they have sold 1.2 million total. Given those two data points, you'd estimate that ASUS is selling 90% of their tablets outside the US. That being said, it wouldn't surprise me to find out that ASUS is strong in Asia and that was what was driving their non-US sales.