For those of you who always have to have your hands on the latest software, Microsoft has released the preview for Office 2013. Aside from usual updates, new features, and a few UI tweaks, a big change is that Microsoft has made Office 2013 incompatible with Windows XP and Windows Vista. Windows 7 will still work, and Windows 8 is what it was designed for.
One of the biggest and most interesting features of Office 2013 is "On Demand" streaming. Basically, it lets you use Office on any Windows 7 or above computer that's connected to the internet without having to install Office. So you could go onto any public computer (with Windows 7 or above and an internet connection), use Office and save your documents to Microsoft's Skydrive, and when you log off there's no trace that you just did what you did. Think of it like Google Docs.