• Its eBooks have DRM (filetype: .AZW), but it supports unprotected Mobipocket books (.MOBI, .PRC), .TXT files, HTML, and Word. Some files can be transferred over USB, while others have to be emailed to the special per-device Kindle email. (More on that later.)
• It has a web browser, under the "Experimental" banner.
• You can download text and other files to the device from the web for later storage. I downloaded young master Doctorow's story "Printcrime" from the Overclocked site via the Kindle's browser and was reading the plaintext version in about 45 seconds.
• It can play Audible audiobooks, but cannot download them over the air using the "Whispernet" EV-DO service. They must be downloaded using the Audible manager, then copied to the Kindle via USB.
• The Kindle can play MP3s copied to its internal storage (180MB user accessible) or SD card, but only on random shuffle. Music can be played in the background while you read or shop the Kindle store.
• Kindle also features "Kindle NowNow," a human-powered search query system powered by Amazon's Mechanical Turk distributed work system. NowNow is free.
• Blog subscriptions cost $2 a month with a 14-day free trial. However, you can browse directly to the blog using the "Basic Web" browser for free. Basically, you'll pay for RSS, but not the web.
• Mobipocket DRM'd files will not work on the Kindle.
• PDF is not supported. At all. Even via the conversion process.
• GIF and JPEG are supported filetypes. Hello, manga!
• There are only two fonts: Caecilia and Neue Helvetica, both from Linotype. You cannot select which font to use to read (the book texts are in Caecilia), but can select from six font sizes.
• If you email a document directly to your Kindle, Amazon will charge you a $.10 per document conversion fee. You can choose to avoid that fee by using the free Kindle service that will email the file back to you, which can then be copied via USB. Update: The pay service took about 15 minutes to convert and broadcast a simple text-only .DOC file; the free copy, sent before I sent the identical file over the pay service, has still not arrived. Update 2: Okay, it actually arrived pretty quickly, but routed back to the email I use for my Amazon account, not the one I sent it from. That puts it in the neighborhood of the pay service.
If you are not in a wireless area or would like to avoid the $.10 fee, you can send attachments to "name"@free.kindle.com to be converted and e-mailed back to your computer at the e-mail address associated with your Amazon.com account. You can then transfer the document to your Kindle using your USB connection.
• The shape of the Kindle makes sense when you hold it, but the color isn't all that great. White plastic is going to get dirty, too.
• The conversion by email, both free and pay-for, isn't instant by any means. I'm actually still waiting on my files to show up after about five minutes. It hasn't shown up in the "Pending" list on Amazon.com's Kindle management page, either.
• You can't use the scroll wheel to move down content, even on the web. You must use the page forward and back keys. It's confusing.
• Bonus 16th Update: Having copied over .DOC, .TXT, .RTF, .PDF, .GIF, .JPEG, and .PDB files directly to the Kindle via USB, only the .TXT file showed up for viewing.
The .DOC file I sent over the air to the Kindle arrived as a .AZW, the Kindle format, which implies to me that the only two file formats this thing can read natively are .AZW and .TXT. That's a huge bummer.