Not the least bit worried. Adoption of Windows 8 in general has been slow because people dislike change and the new UI (no start menu) puts them off at first. Eventually people will adopt the new UI and things will move along just fine when people realize that RT is at least as good as what Apple and Google have to offer. It will be an uphill battle as many people are solidly encamped in either iOS or Android and migration will likely be pretty slow, but I firmly believe it will happen. I am a long time, hard core Linux and Android user who is now running one laptop on Windows 8, owns a Surface, and was just today checking out Windows phones. Open minded people will be curious and see if perhaps the new Windows might not have something to offer them.