In the US, 83 percent of consumers plan to keep their landline phones, even if they also own mobile phones. But on a worldwide basis, the cell phone market is now showing its fastest growth since 2006, according to new research.

New analysts' surveys making the rounds late this week may not entirely conflict with one another, though they are presenting different pictures of complex patterns on the topic of mobile phone adoption.

One simple fact is clear, however: Although mobile adoption is booming overall, the vast majority of the growth is happening in emerging markets outside of the US, Canada, and Western Europe.

"Emerging markets in Asia and Africa continue to surge and they are compensating for the sluggish demand in developed regions of North America and Western Europe," according to Bonny Joy, an analyst at Strategy Analytics.

From January to March 2008, global mobile phone shipments rose 14% from last year's first quarter to 282 million in this year's quarter, say the results of a St5ategy Analytics study.

In its Worldwide Quarterly Mobile Phone Tracker, analyst firm IDC just released very similar findings, pointing to worldwide shipments of 291.6 million mobile phones during the first quarter of 2008, for a year-to-year increase of 14.3%.

According to IDC's numbers, the world's top five mobile phone vendors, in terms of first quarter shipments, landed as follows: Nokia, with a 39.6% market share; Samsung, with 15.9%; Motorola, with 9.4%; LG Electronics, with 8.4%; and Sony Ericsson, with 7.6%.

But elsewhere in Strategy Analytics' reports is data revealing that over two-thirds of mobile operators in Western Europe saw their profit margins fall during this year's first quarter. In fact, emerging markets outside of areas such as Western Europe and North America accounted for 90 percent of growth for mobile operators worldwide.

"The problem is most acute in Western Europe, where profitability peaked in mid-2006," according to David Kerr, vice president of Strategy Analytics' Wireless Practice.

Then again, the Western European mobile market isn't exactly one and the same with the US market, where wireless network technology is still playing catch-up. New survey results from KRC Research imply that many US consumers still prefer landline phones to mobile phones on the basis of voice quality and "reliability" of connections.

A total of 83% of those surveyed in the US nationwide study said they plan to keep their landline phones "indefinitely." Another 12% said they might disconnect their landline phones within a year, but only 2% said they will definitely turn off their landline phones within a year. The remainder were undecided.

Among those using both landline and mobile phone service, 74% said their mobile phones were better than their mobile phones in terms of voice quality, reliability, and "consistency of service."

KRC's study was sponsored by Verizon, a land line service provider that's also a partner in cellular service provider Verizon Wireless. According to a statement from Verizon, the survey participants who also used cell phones subscribed to services from a variety of US mobile providers.