With Surface RT little above 1 million figure and Surface Pro, which debuted a month back, 400,000, Microsoft sold 1.5 million devices and counting. Microsoft Surface GM Panos Panay mentioned recently that Surface Pro demand was higher than whatever they had expected. Microsoft had initially Surface Pro supply issue especially with 128GB model and which got resolved only recently. Now being Surface opened to more markets globally, I think it would meet Microsoft’s expectations eventually. http://www.theverge.com/2013/3/14/4105722/microsoft-surface-sales-1-5-million-rumor
Even Surface RT 64GB and then 32GB also had initial supplies issues, but eventually Microsoft caught up with it.
It would be interesting to see whether Microsoft would release a 7 to 8” Surface device and a Surface book (touch enabled laptop) later this year. The hardware quality of Surface is really beautiful and if they had added GPS sensor in both RT and Pro models, it would’ve been more hit. Now I am looking for an RT device (either from Microsoft or its OEM partners) with digitizer and pen support. It should have gotten that. I hope Lenovo would release it. Lenovo released good number of hybrids with both RT and Windows 8 platforms.