CloudOn is a well reviewed utility that brings MS Office apps to your iPad. The app allows you to access your workspace on a server and use the software remotely, allowing you to open your files directly form your iPad email, Dropbox and Google Drive accounts. Not only can you open, review, create, and edit Microsoft Word, Excel and PowerPoint on your iPad, you can also view, PDF, JPG, PNG and GIF files. When your finished editing your docs, you can then share them to others via email, or to your Dropbox and Google Drive accounts from within the workspace. Until Microsoft comes up with an app for iOS this might just do the trick in the meantime.
Check it out at the Apps store if you really need to use MS Office on your iPad: https://itunes.apple.com/us/app/cloudon/id474025452?mt=8
Create your account or find out more at the CloudOn web site: http://www.cloudon.com