Adobe PDF e-Books can have a preview on Windows Seven, if Adobe Reader is installed.
Similar stuff is present in Windows 7 for a lexicon of filetypes: Supported file types for thumbnails/previews - ResourceSpace Documentation Wiki
But, unfortunately enough, we still lack a tool/ third-party app to enable thumbnail previews for other filetypes, that we often use in daily life, (for example *.pdb, *.chm, *.epub ebooks etc). Even if, we have a third-party viewer installed for all of them, the thumnail preview never appears (instead, they take up the filetype-icon)
Many Media files can have icons with appropriate players/codecs installed: FAQ - Thumbnails
But, works need to be done for the e-book sector.
Similar issues have been already addressed here on this forum, so I don't think, our experts can't make it.
Photoshop PSD files - Enable Thumbnail Previews - Windows 7 ForumsView Photoshop PSD files in Windows - x64 PSD CODEC for Windows 7, Windows Vista
Fixes for 64-bit Adobe Reader preview handler and thumbnails
Some More Resources from Microsoft are Linked Here:
Thanks everyone. I am new here, If I've broken any forum rules, please pardon me, and teach me the proper way.