If you are a Google Chrome user and you haven't disabled the built-in PDF plugin, you can now open PDF attachments from Gmail using your browser's viewer. Just click "View" next to the attachment and you'll notice that the PDF file opens faster and it looks much better.
If you disable the plugin or you use a different browser, Gmail continues to open PDF attachments using the Google Docs Viewer. Maybe Gmail should also detect Adobe Reader's plugin and use it instead of the online PDF viewer.
Google informs that this feature alongwith under mentioned feature will be available in Google Apps, Google Apps for Business, Government and Education on February 22. You can get it faster by enabling "pre-release features" in the Administrator Control Panel.
- Visible Bcc: Gmail will now provide email recipients an indicator when they are added via Bcc on an email. We will add a visible Bcc header only to messages sent from another Gmail user, not from external sources. Each Bcc recipient will only see themselves on the Bcc list.
[Source, Via: Alex]