With the Verizon Wireless stock currently witnessing its highest valuation levels in last ten years, thanks to the news about the forthcoming launch of the popular Apple iPhone on the carrier's CDMA network, Wall Street is abuzz with speculations about how beneficial the iPhone will turn out to be for the carrier.

Despite the fact that the Verizon version of the iPhone is largely being projected to sell nearly 10 million units this year, it has been particularly noted that the handset will initially be highly dilutive to the carrier's 2011 earnings - more so as the company will have to shell out subsidies to Apple.

As such, it is not yet clear as to whether the Verizon iPhone will be able to spark growth in average revenue per user (ARPU), which happens to be one of the most closely watched metrics in the wireless business.

With uncertainty looming large about whether the Verizon iPhone will help the carrier merely retain more of its current subscribers or whether it will help Verizon expand its subscriber base, investors are hopeful that a growth in ARPU could probably be in the offing.

With Verizon shares having increased over 30 percent in the past six months, Oppenheimer's Tim Horan said in a Wednesday interview: "Because there is not as much subscriber growth available as there once was, the hope now is that--if the carriers can cap data usage--users will pass those caps and drive up revenue."