Um no, it is installing just Installer! I mean it even patches the TIFF exploit for you!. If you want to check for "who knows what else it is installing" just SSH to your phone and check.
After unlocking, you go to the "Unlocking Tools" section in Installer that you added to install anySIM and there are some certificates for youtube. I installed them and youtube now works perfectly.
Also, someone said that jailbreakme was updated, and that supposedly youtube now works right of the bat.