When uploading IP.Board 3.0.0 to my server, I noticed several thumbs.db files in the distribution package. They are present as of a couple of minutes ago.
After doing a quick search in the .zip archive, I found a total the total of 14 thumbs.db files with a combined (uncompressed) filesize of 530 KB. While they don't pose a threat or concern, it might be worth removing them as they serve no purpose in the package.