Microsoft will put its Windows 8-based Surface tablet on sale Friday, and analysts are trying to get a read on its prospects. "We can definitely gauge it by chatter. There is a slight learning curve, so I don't think we will see that big pop that iPad saw," said Emily Chan, a Bernstein Research analyst. Microsoft will be hindered at launch by a lack of applications, although the company said it has tripled its inventory in recent weeks. In a BBC interview, Microsoft CEO Steve Ballmer reiterated the company's intent to build more hardware.