I've done my iPad, as atrial before taking the plunge with the phone, and it is different as ever, probably better, but frustrating initially. Inevitably, some of the improvements won't be useful until the mac is on Mavericks, as in previous upgrades. Some features still not available in UK.
Just be careful of the default setting for the control centre to be available when locked - see below.
BBC News - Security holes unearthed in Apple's iOS7