First, it was Nokia. Back in January, a Canalys report revealed that Google’s Android operating system replaced Nokia as the top smartphone platform, based on shipment data on the fourth quarter of 2010. In fact, shipments of Android-based smartphones totaled 32.9 million, while devices based on Nokia’s Symbian platform were at 31 million.

Now, the HTC Thunderbolt is fast becoming Verizon’s most popular phone, despite the fact that the Android smartphone has been on the market for less than two months. According to research from BTIG analyst Walter Piecyk, of 150 Verizon stores around the country, 61 percent reported that they’re selling iPhones and Thunderbolts in equal amounts. However, a whopping 28 percent said the Thunderbolt is selling better, while a mere 11 percent said the iPhone is selling better.

The fact that the HTC Thunderbolt is selling like hotcakes should come as no surprise. For smartphone users that have grown tired of staring at a loading bar, the Android device features a 4.3-inch touchscreen, 8 GB of flash memory, a 1GHz processor and the power of Verizon’s new 4G network. Priced slightly higher than the iPhone 4, the HTC Thunderbolt retails for $249.99 with a two-year contract.

As reported earlier by TechZone360.com, in fourth quarter 2010, the volume of Google OS-based smartphones – which include Android, OMS and Tapas – increased by sales from vendors such as LG, Samsung, Acer and HTC. The sales volume for each of these four companies increased 4,127 percent, 1,474 percent, 709 percent and 371 percent, respectively, when comparing year-over-year amounts.