We get it. Amazon.com's (Nasdaq: AMZN) Kindle is huge.

Amazon announced today that Kindle books have been outselling the e-tailer's print books since April.

You may have seen similar missives by Amazon in the past. Declarations in the past have been limited to hardcovers, paperbacks, or best-seller lists. No more. Amazon's e-books are outselling the store's traditional books across all platforms by 5% since last month.

Oh, and before you ask, Amazon isn't including the popular free e-books that Kindle owners love to gobble up in this question. We're pitting premium e-books against all of its hardcover and paperback editions.

Any other cynics wanting to take a shot? You in the back. What've you got?

"Kindle books are only growing in relative popularity. Print's dying, dude."

Not so fast. Amazon claims that its print book sales continue to grow. Overall book sales may be declining at Barnes & Noble (NYSE: BKS) and Borders, but Amazon's mailing out a record number of books the old-fashioned way. Amazon's just selling more of its digital reads. It has already sold three times as many Kindle books this year as it did at this point in 2010.

The popularity of the recently introduced ad-supported Kindle at a wee price is also making Amazon's platform more mainstream. The $114 reader is now Amazon's best-selling Kindle. Yes, even throwback bibliophiles will put up with sponsored screen savers to save $25 on a Wi-Fi e-reader.

This has been a good week for fans of the print migration. Shares of New York Times (NYSE: NYT) popped higher after announcing the initial success of its digital content pay wall. Folks are paying real money for virtual books and newspapers articles. Nice!

Amazon has become the Netflix (Nasdaq: NFLX) of books. Studios may detest Netflix's digital streaming as much as publishers hate yielding control to Amazon's digital bookstore, but in the end they have to play along if they want to get noticed.

Things are bound to get even more interesting if Amazon comes out with its inevitable tablet. CEO Jeff Bezos has already told analysts to "stay tuned" in that regard, and it would give Amazon a multifunctional gadget to finally give Apple's (Nasdaq: AAPL) iPad 2 a serious competitor.

Amazon's selling a ton of digital books these days. You didn't think it would end there, did you?

Will we ever see publishers offering fully subsidized Kindles? Share your thoughts in the comment box below.

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Longtime Fool contributor Rick Munarriz has been a Kindle owner since 2008 and an iPad owner since last April. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. He does not own shares in any of the companies in this story, except for Netflix.