Apple's (Nasdaq: AAPL) iPad, introduced this weekend, is a decent alternative to the Kindle, Barnes & Noble's (NYSE: BKS) Nook, and varying tablet PCs from Sony (NYSE: SNE) and Hewlett-Packard (NYSE: HPQ). But for all the hype that surrounds this latest bit of iCandy, Amazon.com (Nasdaq: AMZN) may outdo all except Apple in reaping benefits from the iPad.

Why? The Kindle app for the iPad is every bit as good as Apple's iBooks, yet its inventory boasts 7.5 times as many titles at launch: 450,000 versus 60,000, according to media reports. Apple also failed to reach an agreement with publisher Random House before shipping the iPad, which means eager readers will need the Kindle app or a custom alternative from Kobo to download work from The Da Vinci Code author Dan Brown and other Random House writers, The Wall Street Journal reports.

Except for some bells and whistles, there appears to be little difference between Kindle for iPad and iBooks. Both are elegantly animated and use the device's bright display to maximum effect. Both allow for bookmarks and other standard features you'd expect in an e-reader.

And that's important. By making an app that's every bit as good as iBooks, Amazon fulfills a strategy CEO Jeff Bezos first talked about a Wired conference last June, in which he announced that he'd separate his company's e-bookstore from the Kindle.

"Separating the hardware from the store means that even if Apple does come out with a killer tablet, users would still have the option to buy from Amazon thanks to the Kindle Reader for iPhone -- and Amazon is likely to have the greater ebook selection," I wrote at the time.

Now that day is here and ... Amazon's is the biggest bookstore on the iPad. Surprise!

To be fair, having Kindle editions on the iPad isn't likely to mean much to Amazon over the short term. But over time, the iPad could become a huge and very profitable channel for the e-tailer, especially if Amazon and publishers reach a mutually beneficial accord on ebook pricing.

It's almost certain they will. Amazon has little choice but to do what it can to make publishers happy, and publishers aren't exactly swimming in profits right now. They need Apple and Amazon to succeed in selling ebooks.

With the iPad, that job just got easier.

Will the iPad live up to the iHype? Discuss in the comments box below.