The retailer, which also benefited from a $53 million gain from the sale of some European DVD rental assets, defied the weakening US economy to report a $158 million profit for the period, although the sales growth was driven by sales abroad.

Furthermore, Amazon said that sales could reach $20.1 billion for the year, slightly ahead of the maximum prediction of $20 billion earlier in the year. The retailer expects full-year profits of $745 million to $920 million.

The second-quarter profit, which equated to $0.37-a-share, beat analysts estimates by $0.11, and compared to $0.19-a-share profit income a year earlier. The group’s overall revenues increased by 41 per cent to $4.06 billion. Meanwhile, international sales rose by 47 per cent to $1.89 billion. Without the impact of the weak dollar, overseas revenue grew by 34 per cent.

So-called media sales, which comprise items such as books, CDs and DVDs, rose by 31 per cent to $2.41 billion across the group, while electronics and general merchandise recorded a 58 per cent jump to $1.53 billion.

Scott Devitt, an analyst with Stifel Nicolaus, described the results as being “good, very solid”.

Amazon may also be benefiting from the soaring cost of petrol, according to Dan Geiman, an analyst at McAdams Wright Ragen.

“They’re still doing extremely well [despite the economy]. If gas prices are high, customers are less likely to hop in their cars and head down to the Barnes and Noble or a department store.”

Jeff Bezos, founder and chief executive of Amazon, also seemed pleased with the results.

“Customers continue to take advantage of our low prices, free shipping and Amazon Prime. Amazon Prime membership costs less than a tank of gas – more and more customers are joining the programme and enjoying its benefits.” Prime Membership offers free two-day shipping of items for an annual fee.

“They spent a ton of money on this thing and it is natural they want to make a return,” analyst Rob Enderle of Enderle Group in Silicon Valley said.

Google has bided its time working on ways to “monetize” YouTube without alienating notoriously transient Internet users that could easily switch to Hulu, Daily Motion or other rivals in the online video-sharing arena.

“Click-to-buy” links are being discretely placed in control panels below YouTube videos to invite people to visit online shops iTunes or Amazon.com to buy music, books, films or other material related to snippets watched.

“This is just the beginning of building a broad, viable e-commerce platform for users and partners on YouTube,” said a message on the website.

“Our vision is to help partners across all industries offer useful and relevant products to a large, yet targeted audience, and generate additional revenue from their content on YouTube beyond the advertising we serve against their videos.”

Links to online stores are making a U.S. debut on videos of EMI Music artists and of the Spore computer game recently released by Electronic Arts.

Amazon.com has said that the new artist stores serve as one-stop destinations for all things related to musicians and their music. Customers can learn about their favorite performers through images and biographies, discover music in any format, listen to song previews and even contribute to artist profiles.

Additionally, Amazon Artist Stores reportedly have more than just music, featuring related merchandise such as concert shirts, rare posters, books, and concert DVDs.

Peter Faricy, vice president of music and movies at Amazon.com, said: “We have always understood that our customers want to listen to their music when they want it, where they want it and in whichever format they want it. We are music lovers here at Amazon, and we created the Amazon Artist Stores for everyone from the casual enthusiast and occasional gift-giver to the seasoned music junkie. These stores allow our customers to easily find and discover the music they love in any format along with a variety of artist content, like exclusive music videos and behind-the-scenes footage, all in a single place.”

Play.com and Amazon beat high street rivals according to the survey by the National Consumer Satisfaction Index.

Out of 6,000 shoppers questioned, Play.com came top with a rating of 87 out of 100. Waitrose was the favourite bricks and mortar retailer with a score of 82.

The worst-scoring retailers included electricals chain Currys and Somerfield, which came bottom with a score of 61.

Chief executive of consultancy CFI Group Sheri Teodoru said:  “As the economy slows, the big challenge for retailers of all types will be how to compete to retain shoppers who are becoming increasingly conservative with their spending.

“Here customer satisfaction is key: companies that provide the most satisfying experience stand the best chance not only to survive, but to thrive financially in a down economy.”