Originally Posted by ElizabethN
If I didn't delete the azw file then a revised azw file was sent to the device, even though a mobi file was also present. Without opening calibre, I can't remember if it sends over azw before mobi files if both are present.
I believe it does send the azw file by default. Just in case you are not aware of it, however, there is an option to send a particular format to the Kindle. Simply right-click on the books you want to transfer, mouse-over "Send to Device", and then go to "Send Specific Format To" and "Main Memory." When you click on that, it will pop up a screen asking which format you want sent to the Kindle. Simply choose mobi and that should do the trick.
I'll try to get the next version posted this weekend. Unfortunately the holidays have been a bit hectic otherwise I would have gotten that done earlier.