Few are expecting the world's most valuable technology company -- which surpasses Wall Street expectations with near regularity -- to deliver a bumper quarter once more on Tuesday.

The main reason: consumers holding out for the new iPhone.

Apple (AAPL.O) may still surprise market watchers, but many Wall Street analysts and investors remember how chatter over the launch of a new iPhone last year caused Apple to miss quarterly expectations in the fall, for the first time in years.

The iPhone 5 is only expected to hit store shelves around October -- just in time for the holidays -- with a thinner, larger screen and fine-tuned search features. Couple that pre-launch lull with slowdowns in Europe and China, Apple's biggest markets outside of North America, and sentiment on the Wall Street darling is more muted than many can remember in a while.

"No longer is Apple the company that beats every time," said Tim Lesko, portfolio manager at Granite Investment Advisors, which owns Apple stock. "I expect Apple to beat Apple's guidance, but I don't know whether they will beat Wall Street's guidance."

Tony Sacconaghi, analyst with Bernstein Research, sees a reasonable chance Apple will miss expectations on revenue, citing "macroeconomic weakness in China and Europe, a product cycle lull in the iPhone, a later than expected introduction of the new iPad into China, and the late quarter introduction of new Mac notebooks."

Any hiccup in demand for the best-selling smartphone can have a big impact on both revenue and profits as the five-year old device accounts for nearly 50 percent for Apple's revenues. And it comes at a time Samsung (005930.KS) and other manufacturers that use rival Google Inc's (GOOG.O) Android software are chipping away at its market share.

Apple is expected to report fiscal third-quarter earnings of $10.35 a share on revenue of $37.2 billion, according to Thomson Reuters I/B/E/S.

Top Wall Street analysts are betting the numbers will undershoot that. Apple may miss the average sales forecast by about 0.2 percent, according to Thomson Reuters Starmine's SmartEstimates, which places greater emphasis on timely forecasts by top-rated analysts.

IPAD'S LAUNCH IN CHINA

But some analysts also think the Street is underestimating the impact of a late iPad launch in China, a focal point of intense expansion for the company and a huge driver of growth.

Apple began selling the tablet there on Friday, but many had expected it to ship last quarter.

Sales in China, Hong Kong and Taiwan jumped threefold to $7.9 billion in the second quarter, accounting for about 20 percent of Apple's $39.2 billion in total revenue.

The company typically introduces a new iPhone every year, but has yet to reveal any details on the next model.

However, people familiar with the situation have told Reuters the new iPhone will have a bigger display and that Apple has begun to place orders for the new displays from suppliers in South Korea and Japan.

Meanwhile, Apple's iPhone 4S is just three quarters old, which is relatively new by any standard. But many fans of the phone now see it as a cyclical product with somewhat predictable launch timeframes, preferring to wait a few months to buy the new model, analysts said.

Wall Street estimates Apple sold about 29 million iPhones, down from 35.1 million sold in the March quarter. Sales of the new iPad, expected to be 14 million to 15 million, is likely to offset part of the anticipated sequential drop in iPhones sales.

Apart from concerns about iPhone purchases, Wall Street is worried about the rising prominence of Google and Amazon.com (AMZN.O) in the mobile market, particularly with the launch of Google's smaller and cheaper Nexus 7 tablet, which is gaining popularity.

Still, no one is bearish in the longer term on the world's largest technology company by market value and most Apple watchers believe the company will make up any lost iPhone volume during the holiday season.

"Big picture, it doesn't matter," said Sterne Agee analyst Shaw Wu. "They are still the share gainer in the larger scheme of things. This is clearly a timing issue."

BIG HOLIDAY SEASON EYED

Wall Street expects that the outlook for this year's holiday season will be enormous for Apple as it may include the launch of a new iPhone as well as a potential new "mini iPad."

Apple has been working on a smaller tablet, a person familiar with the matter told Reuters.

It is unclear when Apple will launch such a tablet, but some clues are emerging on the timing of the new iPhone.

When Verizon -- one of the wireless carriers that work with Apple -- was asked on Thursday why customers have been holding back on handset upgrades, CFO Fran Shammo said: "There is always that rumor mill out there with a new phone coming out in the fourth quarter and so people may be waiting."

Investors will pick apart executives' comments for clues to new product introductions. While Apple has a policy of never giving advance details or timings on new products, Chief Financial Officer Peter Oppenheimer has often hinted of "product transition" in earnings conference calls preceding a launch.

Wall Street estimates Apple sold about 4 million Macintosh computers as the PC market saw growth sputter in the quarter.

The lackluster expectations do not appear to have affected Apple's stock, which is up nearly 50 percent so far in 2012. The stock has been choppy since a high of $644 in April. It closed Friday at $604.30 on the Nasdaq.

"Of all the quarters, this is the one that seems to have widest range of opinion," said Granite's Lesko.

(Reporting by Poornima Gupta, Editing by Gary Crosse)

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