http://www.kobobooks.com/touch_tech
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Supported File Formats Books: EPUB, PDF and
MOBI
Documents: PDF
Images: JPEG, GIF, PNG, BMP and TIFF
Text: TXT, HTML and RTF
Comic Books: CBZ and CBR
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Geeky, This is from KOBO official Technical Specifications site. But anyway, same thing you can find on any Reviw and Technical Specifications site. There is always MOBI as one of supported formats.
But sa I said before, 60% of the text is OK, 40 % is just a garbage. like is rendered wrongly or ... I dont know!!