Back in March, we reported that .mobi domain names had hit the 400K mark. The dotMobi registry announced this week that they've now crossed the 500K mark:

dotMobi, the registry
for .mobi domains, today announced that 500,000 .mobi domains have been
registered in 104 countries since the domain's commercial launch in
October 2006.

…

Many auto brands, such as bmw.mobi, ferrari.mobi and rolls-royce.mobi, news and entertainment players such as espn.mobi,
maxim.mobi, foxnews.mobi, businessweek.mobi and cnnmoney.mobi and
mobile operators including Telecom Itali mobile division TIM and
Bulgaria's Vivatel, have all registered .mobi domains, says the company.

“The
results demonstrate the strong role dotMobi is playing in driving the
creation of mobile content on the Internet,” says Neil Edwards, CEO of
dotMobi. “Most importantly, the mobile industry's consumer focus around
creating .mobi sites is bearing strong results in a short period of
time. Consumers finally have easy-to-use and affordable made-for-mobile
content.”