Updated from 9:44 a.m. ESTApple's ( AAPL) bountiful holiday quarter gave its stock a growth spurt on Thursday. But analysts differed on whether the share price would continue to grow or taper off. In recent trading, the company's shares were up $6.35, or 9.7%, to $71.81. Prudential's Steven Fortuna had one of the sunniest forecasts, pushing up his price target to $93 from $75, and upgrading Apple to an "overweight" rating from a "neutral." "Although we typically are not reactive to company earnings, we are taking exception here as a result of the magnitude of the upside surprise and the accompanying upward revision to earnings. We believe that the company may have begun a market share breakout story that could last for the foreseeable future," Fortuna said in a research note issued on Thursday. (Prudential has not done recent investment banking business for Apple.) But others saw little upside in the stock after its big run on Thursday morning. Harry Blount at Lehman Brothers, for instance, took his price target up to just $73 from $66 and maintained his "equal weight rating on Apple shares. "While we believe that Apple will maintain strong product momentum, we believe the flow of good news has likely peaked short-term. Therefore we are increasingly wary of valuation," Blount said in a report on Thursday. (Apple has been a noninvestment banking client of Lehman in the last year.) In its first quarter ended Dec. 25, Apple earned $295 million, or 70 cents a share. That was more than quadruple the $63 million, or 17 cents a share, the company earned in the same quarter a year ago. Sales at the Cupertino, Calif.-based company jumped 74% to $3.49 billion. In contrast, analysts had predicted that Apple would post earnings of 49 cents a share in its just-completed quarter on $3.18 billion in sales, according to Thomson First Call. And it was above the guidance Apple gave in October, when the company projected it would earn 39 cents to 42 cents a share on sales ranging from $2.8 billion to $2.9 billion.