Hey lolitajoon,
Thanks for the question. You are correct, comments are hidden from all iWork apps when imported to iWork for iCloud beta. Please note that the current release of Numbers for iCloud is a beta version. Therefore, certain features aren’t yet supported.
Opening iWork files in iWork for iCloud beta
http://support.apple.com/kb/HT5663
Features that behave differently after importing your document
These features behave differently in iWork for iCloud beta. They don't change in the original copy of your iWork for iOS or iWork for Mac document.
Importing from all iWork apps
- Comments are hidden.
Additional information:
Numbers for iCloud beta: Coming soon in Numbers for iCloud beta
http://support.apple.com/kb/PH12840
Thanks,
Matt M.