The line between search and social is continuously blurring, especially as Google and Facebook become more similar with new features that boost the search engine’s social connectedness and the social site’s search options.

The recent buzz surrounding Google’s potential social site Google Me as a Facebook competitor and Facebook’s ever-evolving search features, including Facebook Questions and the new Wowd application, indicate that the two are trying to expand their appeal among internet users and online marketers. Now, the latest website rankings from Hitwise show that the competition is heating up.

Hitwise reports that in the first week of August (ending on the 7th), Facebook triumphed as the leading website for “All Categories.” The social site garnered 9.47 percent of web visits. Google followed closely, accounting for 7.38 percent of all visits last week.

At the same time, Google beat out Facebook in the industry clickstream during the same period. The search giant represented nearly one-fifth of all clicks (19.46 percent). Facebook came in second, accounting for 11.24 percent of clicks. However, it is worth noting that the leading clicked search term for the industry “Computers and Internet – Social Networking and Forums” was “Facebook.”

“Facebook” was by far the leading query in this category in the four-week period ending August 7, generating 12.47 percent of search clicks. “Facebook login” ranked as second, representing 4.76 percent of search clicks. Additionally, “facebook.com” and “www.facebook.com” both made the top 10 list, representing 1.66 and 1.33 percent of clicks, respectively. Google’s social video platform “YouTube” came in third, with 4.01 percent of search clicks in this category.

With this in mind, marketers may understand that both Google and Facebook are valuable channels for reaching online consumers. Plus, both are ramping up their ad options – from Inside AdWord’s recent updates to the Keyword tool to Facebook’s user-review ad format currently being tested. Marketers can take advantage of such competitive offerings to reach consumers on these popular web destinations.

A number of marketers are anticipating investing more heavily in Facebook advertising next year, with AdAge relaying that research firm eMarketer predicts ad spend on the social platform will exceed $1 billion in 2011.