You can think of Microsoft Office 365 as Microsoft’s answers to Google Apps that aims to serve both enterprise customers as well as small businesses.
Microsoft Office 365 is a cloud-based solution so organizations don’t have to install anything and yet they have access to services like Microsoft Office Web Apps, Exchange and SharePoint delivered online.
Office 365 for small businesses with fewer than 25 employees will get Office Web Apps, Exchange Online, SharePoint Online, Lync Online and an external website for $6 or 5.25 Euros per user, per month.
Unlike Google App which is cloud-only, enterprise customers of Office 365 will also have the option to get Microsoft Office Professional Plus desktop software on a pay-as-you-go basis or $24 or 22.75 Euros per user, per month so that they work offline as well.
Office 365 will be available worldwide next year. You can sign-up for the Office 365 beta at office365.com.