After January's long-awaited touchscreen rollout, BlackBerry (BBRY) is ready for this year's Act Two: the physically keyboarded Q10, which might arrive in the U.K. Friday. The firm faced criticism by loyalists over its decision to release the touch-screen Z10 first (as well as reports of mass returns). But can the Q10 sell enough to loyal keyboarders and upgraders to make a splash in a consistently shrinking side of the market?