Last week, Mint has released version 17.3 (code named Rosa). It can be downloaded from the Linux Mint website (http://www.linuxmint.com/download.php)
For those who are already having the earlier version 17.2 (Rafaela), all you need to do is upgrade using the Update Manager application.
I have upgraded my Cinnamon 17.2 to 17.3 today and have captured the screen shot of this simplest process.
I had earlier replaced my startup and shutdown Mint logo with a custom png image which now got overwritten after the update. Hence I had to redo the process:
I replaced the image –/lib/plymouth/themes/mint-logo/logo.png with a new one after which I ran the command from terminal
sudo update-initramfs -u
Now, It uses my image when starting up and shutting down.
New features are listed in Linux Mint site: http://www.linuxmint.com/rel_rosa_cinnamon_whatsnew.php