Though the Conficker worm watch was mostly for naught, among the data rolling in from Wednesday's activity is an OpenDNS report that says 500,000 of its customers were infected with the worm's latest variant. "That number is more than I expected," says David Ulevitch, founder of OpenDNS. "We're not representative of the whole Internet, of course, but to me this indicates the infection for [Conficker] is probably larger than people expected."

OpenDNS, which provide a domain name service offering, also found that among its customers, Vietnam has the highest rate of Conficker.C infection, with 13.3 percent; followed by Brazil, 11.6 percent; the Philippines, 11.1 percent; Indonesia, 10.9 percent; Algeria, 7.3 percent; the U.S., 4.7 percent; and India, just less than 4.7 percent.

Vietnamese researchers at security firm BKIS, meantime, reported earlier today 1.3 million Conficker.C-infected machines. BKIS found that worldwide, China has the highest rate of infection, with 13.8 percent, followed by Brazil (10.4 percent) and Russia (9.3 percent), and with the U.S. in the 2 percent range.

British Telecom, meanwhile, said it detected more than 25 Conficker.C worm infection incidents among its U.S. customers' networks.

"In general, the level of sophistication of Conficker is impressive," OpenDNS's Ulevitch says. "It will continue to evolve to evade detection...but we haven't seen it doing anything malicious yet. It's scary in that regard."

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