A blog detailing a little more about Windows Blue has been posted by Microsoft:
The inclusion of a new Start icon is mentioned along with details concerning:
Personalisation,
A better search function,
Improved keyboard and mouse options,
Internet Explore 11,
Cloud Connectivity,
Apps and...
app
cloud connectivity
enhancements
improvements
internet explorer
keyboard settings
microsoft
mouse settings
pc configuration
personalization
search function
starticon
store improvements
windows 8.1
windows blue