-By Steve McClellan, Adweek

After years of lagging behind European countries, the U.S. is poised to take the top spot for mobile Web usage by month's end, according to data collected by technology firm Bango, which provides mobile Internet access platforms to 100,000 Web sites worldwide.

In July, Bango reported the U.K. was top-ranked in mobile Web usage, accounting for almost 19.4 percent of the worldwide total, just ahead of the U.S., which collected about 18.9 percent of total usage. Rounding out the top five were India (10.8 percent), South Africa (8.8 percent) and Indonesia (4.1 percent).

But according to Adam Kerr, Bango's vp, North America, U.S. usage in recent weeks has increased 4 percent while U.K. growth was about 1 percent. When the final numbers are tallied for August, Kerr expects the U.S. to surpass the U.K. in usage with close to a 23 percent share of the total mobile Internet market, leaving the U.K. with slightly more than 20 percent.

Why the change? Kerr cites several reasons, including the fact that U.S. mobile carriers are rapidly building out 3G networks, which facilitate the transmission of mobile Web-based video at faster rates, something that U.K. and other European-based carriers did years ago. Plus, newer handsets available in the U.S. offer higher quality reception of video and music and cheaper subscriber plans have boosted sign-ups among consumers, he said.

The most highly trafficked sites tend to be those offering news, sports and weather, with spikes occurring during rush hour and lunch breaks. "Growth in the U.S. has really come on strong in the last two years," he said.

The increased usage will attract more ad dollars to the space, per analysts. For example, eMarketer predicts mobile advertising will grow fourfold from $1.6 billion in 2008 to $6.4 billion in 2012, with Internet video becoming the most lucrative mobile ad channel by 2010.