Ever since SharePoint 2013 is released, there's increased demand from partners and customers on feature comparison matrix between different versions of SharePoint: 2007, 2010 and 2013. They need it so that they can make informed decision about upgrading their existing SharePoint to the latest version.
Unfortunately, there isn't any official tabular matrix that provides this kind of comparison. However, I've compiled a list of links that provide you new and changed features. You can use this list and create your own matrix. Feel free to comment if you know additional links in this regard.
Matrix created by third parties or other bloggers (you might want to verify for comprehensiveness and correctness)
Now, when you are on path to 2013, you would also need comparison between various Editions of SharePoint (Foundation, Standard, Enterprise) and various plans for Office 365 and SharePoint Online. Fortunately, TechNet has provided a very useful and detailed tabular matrix for this comparison.
There’s just one URL for all such comparisons: SharePoint Online. Each feature in these tables is a hyperlink to another page, which provides your description of that feature. It contains the following sections:
The above page is huge list with a long scroll bar. If you are interested for specific area, there are individual pages also. I’ve provided a tabular format for your use
If you want it be available in offline excel copy, Andrew Connell has done the good work to compile above information in a spreadsheet with filterable columns. you can find that here: SharePoint 2013 & Office 365 Feature Matrix–An Easier Way to View It. At the same time, you need to be aware that excel might not be updated always as Office 365 would be adding new features every three months.