Amazon.com, Inc. (NASDAQ:AMZN) has published a press release today that reveals that their customers are buying more Kindle books than print books (hardcover & paperback) from them. Amazon.com started selling books in July 1995. The original Kindle was released in November 2007.

Gartner, Inc. (NYSE:IT) has reported that about 428 million mobile communication devices have sold across the world in Q1 2011, which is a 19% increase year-on-year.

It was reported recently that Apple Inc. acquired the domain name iCloud.com and that they have signed a deal with EMI Music and other record deals. Today an Apple patent from Q4 2009 surfaced by PatentlyApple.com reveals that Apple has been working on the cloud based media service for nearly 2 years now.

LinkedIn Corp (NYSE:LNKD) went public today and their shares have surged over 100% during mid-day trading. The company priced their IPO at $45 and the stock opened at $83 before settling at about $120 within 2 hours of the trading. LinkedIn raised over $100 million in funding from Sequoia Capital, Greylock Partners, and Bessemer Venture Capital Partners.

The PayPal Android application now has the ability to deposit a check by taking a picture of a check. This feature was available on the PayPal iPhone app late last year. On average about one million dollars is being deposited per month through the iPhone check photo capture feature. Another feature added to the PayPal Android app is “Move to SD card” support. [PayPal Blog]

Gregg Gillis (aka Girl Talk) is a DJ that made the concept of the music mash-up very popular. Girl Talk submitted the track “This is the Remix” to the Tesla Orchestra as part of the Open Spark Project. Artists were asked to submit MIDI files of their music that was turned into the spark tunes. [Wired]

Microsoft Corporation (NASDAQ:MSFT) has released an infographic about how product teams collaborate in social, research, cloud, and natural user interface technologies to the point of developing. [Click on the image to enlarge]

San Francisco based cloud database company ObjectLabs has raised $3 million in Series A funding led by Foundry Group, GRP Partners, Baseline Ventures, Freestyle Capital, David Cohen, and a few others. ObjectLabs is best known for launching the database-as-a-service company MongoLab. MongoLab is the database-as-a-service provider for MongoDB. 10gen‘s MongoDB is used by companies like Foursquare, Bit.ly, and Etsy.