Someone was curious about the double tap home button: Go to settings and then applications, and the last options allows you to change the function.
Also to save some battery for those of you with social networking, I would recommend going to data manager under settings, then data delivery, then social applications. You can set it to only update on wifi, so when you are at home on the charger it syncs.
Edit: to have the phone vibrate for text messages, go to the home of the text messages and pull up the menu, then settings. Should be an option close to the bottom.