According to a report released by Barracuda Labs, Google has twice as much malware than Bing, Yahoo, and Twitter put together. The study was conducted across these web properties over a two-month period.

Barracuda says it reviewed over 25,000 trending topics and nearly 5.5 million search results, analyzing them to identify the types of topics used by malware distributors. The firm will be presenting its findings at DefCON 18 this weekend, but the report is available here (pdf). Barracuda lists the following as highlights from its findings:

- Overall, Google takes the crown for malware distribution — turning up more than twice the amount of malware as Bing, Twitter and Yahoo! combined when searches on popular trending topics were performed. Google presents at 69 percent; Yahoo! at 18 percent; Bing at 12 percent; and Twitter at one percent.

- The average amount of time for a trending topic to appear on one of the major search engines after appearing on Twitter varies tremendously: 1.2 days for Google, 4.3 days for Bing, and 4.8 days for Yahoo!

- Over half of the malware found was between the hours of 4:00 a.m. and 10:00 a.m. GMT.

- The top 10 terms used by malware distributors include the name of a NFL player, three actresses, a Playboy Playmate and a college student who faked his way into Harvard.

- In general, activity is increasing on Twitter: more users are coming online; True Twitter Users are tweeting more often, and even casual users are becoming more active. As users become more active, the malicious activity also increases.

- Only 28.87 percent of Twitter users are actual True Twitter Users.

- Half of Twitter users tweet less than once a day, yet one in 10 users tweet five or more times a day and 30 percent of Twitter accounts have never tweeted.

-  One in every eight Twitter users has at least 10 times more followers than they are following.

-  Only one in 10 users is following more than 100 users, and almost half are following less than five.

- The Twitter Crime Rate for the first half of 2010 was 1.67 percent.

"Our study shows that attackers have serious efforts devoted towards getting in front of the billions of eyeballs that are using search engines everyday and the millions of users that are connecting on social networks like Twitter," said Dr. Paul Judge, chief research officer and VP at Barracuda Networks. "Therefore, we continue to analyze their approaches and build new techniques to find them and protect users."

NetworkWorld points to some market share numbers, which seem to mirror the malware percentages presented by Barracuda.