It looks like Sony has enabled easy access to PSVita's Recovery Menu to perform some "service" tasks such as fixing a corrupted file system, upgrading the firmware, formatting memory sticks and more.
Here is how to access the Recovery Menu :
1- Completely Switch off the PSVita (Press Power Button for 10 seconds, not a standby).
2- Press and hold "R" + Power + PS (PlayStation Button).
Wait a few moments and you'll be greeted with the Recovery Menu, which I need to remind you to proceed with caution through its different functions.
http://www.youtube.com/watch?v=R532NpDMQhw
Here is an image of the Recovery Menu in English (credit to junn)
Here is how to access the Recovery Menu :
1- Completely Switch off the PSVita (Press Power Button for 10 seconds, not a standby).
2- Press and hold "R" + Power + PS (PlayStation Button).
Wait a few moments and you'll be greeted with the Recovery Menu, which I need to remind you to proceed with caution through its different functions.
http://www.youtube.com/watch?v=R532NpDMQhw
Here is an image of the Recovery Menu in English (credit to junn)