A new report from AdDuplex continues to show that Microsoft's Windows RT version of the Surface tablet is the most popular PC among Windows 8 and RT users worldwide. From Neowin:

Today, AdDuplex released their results for the first half of January, and not only is the Surface still leading among all Windows 8/RT PCs, but it actually gained market share. In December, it was at six percent but January's number show it at 7.6 percent. This was likely due to the Surface expanding to more retail outlets in mid-December such as Best Buy. AdDuplex says their numbers come from data collected by 112 Windows Store apps running the company's SDK on Monday, January 14th.

Over 7,400 PCs were running either Windows 8 or Windows R on AdDuplex, compared to 5,500 Windows 8/RT PCs in December and 3,000 PCs in November. This data may show that Windows 8 upgrades on older Windows PCs continue to grow at a solid rate.

 Report: Microsoft Surface continues to rule over other Windows 8/RT devices