The latest to update to Office 365 Exchange Online Services integrates Office web app with Outlook web app. This integration enables users to have a high fidelity preview of email attachments right from outlook web app. The documents that can be previewed from Office 365 Outlook Web App includes word, excel and power point.
This is a welcome addition to Office 365 as users can view attached office documents directly on the browser without having to download the files their desktop.
All the user has to do is click Open in Browser link that is shown next to the attachment in the Outlook web app.
The document will be opened in another window
Though this feature is available with Sharepoint 2010 on-premise, this feature is still not available to Exchange Online. Seamless roll out of features like this only emphasizes the fact that Office 365 is the way to go as organizations get access to the latest version of software without extra license or downtime.