Questions about Siri

Does Siri work locally on the 4S or does it send to a server? Does it require a data connection to work?

Obviously some things (like wikipedia searches) require a data connection, but what about things like setting reminders and alarms? When they talk about dictation in the keynote (1:25:48 on the youtube page), they mention something about "send[ing] it up to the server." If it needs to send to a server just to parse the general words you're saying, I'd imagine it would definitely need to in order to parse for the action behind "Will it be cold in Harrisburg, Pennsylvania this week end?"

However as Siri appears to be exclusive to the 4S, it might be assumed that hardware has a role in it's function.

Thoughts?

 

It requires a data connection for dictation? That is sort of lame. Everything else seems incredible though. I am glad I got my preorder in.