Research in Motion, maker of the BlackBerry device, has profited from stellar growth, but analysts are starting to worry about the company's long-term outlook as it attempts to move into the fickle consumer market. In the company's fiscal fourth quarter, which ended March 1, RIM's consumer subscribers grew an estimated 150 percent from the previous year. However, there are concerns that this growth will not continue as competition from other smartphones escalates. Article (sub. req)