Siri has tight integration with Twitter and Facebook to allow posting to Facebook and Twitter.
Siri User Guide Blog
Assign relationship to your contacts using Siri. Once you get to use Siri a few times, it soon becomes second nature to call or text a contact in your address book.
It’s easy enough to enter a note into your iPhone but of course Siri can make the process much quicker.
Someone has kindly put together a neat video of clips showing Siri displaying its sense of humour.
Find my Friends is a useful app for ‘keeping track’ of your fellow iCloud and iPhone users.
Get directions to a specific location using Siri.
Siri will use Wolfram Alpha to find the answer to an amazing variety of questions.
Whether you’re searching for a haircut, restaurant or supermarket, Siri will be able to find the closest one to you.
You can use Siri to find out what appointments you have coming up at any time in the future.
Here is a great video where ‘Jessica’ asks Siri a few random questions. The results are unexpected.