There is a great new site I just learned about to help you navigate the different offerings in Office 365. The set lets you quickly filter on what your look for. You can find the site here:
Here is what it looks like:
The site offers the ability to look at this in an Excel spreadsheet located here: view the full-size workbook.
For more details you will still want to visit the Office 365 Service Descriptions in the TechNet library.
Sr. Partner Technology Strategist