Very important note: once you get access to your Pi, do regenerate the SSH keys.
Since Raspbian (and basically all the other distributions) are distributed as prepared images to copy onto the SD card, it is not safe to keep the default SSH keys.
To regenerate the keys proceed as follows:
Updating and Upgrading Debian Raspbian “wheezy” Linux Distribution
Before you begin to install any software it’s best to make sure the package index files are up-to-date (essentially just a file pointing to the latest version of compatible software – for example when we install VNC later in the guide). Make sure you have an internet connection and run the following command. It may take a few minutes.
sudo apt-get update
sudo apt-get upgrade
Now’s also a good time to make sure the whole Linux distribution is up-to-date. You can do this now, or later (it may take a while). Again make sure you have an internet connection and run:
sudo apt-get dist-upgrade
You can run these commands every now and again to make sure you have the latest software. If you’re asked to confirm anything, just hit ‘y’ on the keyboard.