Starting on May 4th, Kindle will now be charging users $0.15 per megabyte for files they email to their Kindle via its wireless connection (Whispernet). This is up from the $0.10 charge for files without any size limit. Is this literally nickle and diming? Well, not exactly. I think it’s likely a protective move because the fees that Amazon is paying to maintain the service are more than they anticipated. Any file’s cost will now be determined by rounding up to the nearest megabyte. It remains free to transfer the file yourself via USB.

I hope this is not the slippery slope of charging more for Whispernet services as time goes on, because one of the best successes of the Kindle has been how popular its wireless service is (for example, see this XKCD comic).

But the good news is that now Amazon is supporting RTF and DocX files for their conversion process (albeit “experimentally,” so that they don’t guaranty it will be perfect), whereby you email a file to your Kindle email address and Amazon converts it to a Kindle compatible file (emailing it back to you for free, or to your Kindle for $0.15 a MB). DocX is Microsoft’s latest Word format, which is a default for newer versions of MS Word, while RTF is the old standby and the format that E-Reads uses to maintain many manuscripts in our archives. Good on them for pushing the format envelope a bit more like Sony has been doing.

- Michael Gaudet