Does wireless syncing and iCloud backup use data?

[3GEE]

Hey folks, a very basic question here. Does iTunes wireless syncing and iCloud backup use upload and download data? I have a very small daily cap from my Internet provider and I'm afraid I'll be chewing it up in moments?

These are very cool features but I'm afraid to use them yet. Have I got it all wrong? Should I not be worrying? Thanks.

 

[SOLLERBOY]

shouldn't do, just sends the data to the router and over to the mac, shouldn't up or download anything.

 

[Transeau]

Both are supposed to use run only when on WiFi and charging. Though I have my doubts about the charging. I've caught my 4 syncing several times during the beta while not plugged in.