I thoroughly enjoy using my Microsoft Surface RT and never even considered other RT devices. According to CNET, Samsung won't be bringing their Samsung Ativ Tab to the US due to demand not being as high as hoped and the amount of education Samsung believes they have to invest in to inform consumers about the benefits of Windows RT. While it isn't good news to see manufacturers limiting the rollout of Windows RT, Microsoft may not mind selling more of their own Surface RT devices.
With the Surface Pro coming out soon, I think the educational effort would be even more difficult as consumers, and retail sales associates, still seem to be confused about Windows RT and Windows 8. The Microsoft Surface RT hardware is some of the best I have ever tried on a computing device and its not like there needs to be a huge assortment of RT devices to satisfy consumers. While I understand that the Surface RT is not for everyone, including my ZDNet associate James Kendrick, I previously explained in a post why I find it desirable and think it would have been nice to check out what Samsung came up with. Samsung stated they are going to see how the market develops for RT and they are not permanently shelving their plans.
It's a bit concerning to me that Samsung doesn't see enough value to enter the RT market since they are doing extremely well with Android and I would think they wouldn't mind shelling out some cash to support a new platform if they saw real value in it. Asus, Dell, and Lenovo still have RT products and I think 2013 will be a defining year for Microsoft and its Windows RT platform.