The misprint: The error occurs on page 99, where it reads "eleven 'Outstanding' O.W.L.s" instead of "ten".
Correction: The mistake was corrected in later printings.
Collectibility: This specific error makes the book a rare and sought-after first edition for collectors.
Publication: It is a UK first edition published by Bloomsbury in 2005.
See my photos for the condition, read once and kept on a bookcase.
Thank you for looking.