I am not amused with O2 in all of this.
AFAIK I keep the "unlimited" data package as I've been on Simplicity 20 (iPhone) for the last 6 months (and I'll be buying the iPhone 4 on PAYG, so it's not an "upgrade") but I'm already considering switching networks if they're going to screw customers.
Wasn't it their stance that unlimited meant unlimited, like they've sworn by on their internet campaigns for years? :/
It's fair to say I am disappoint.
P.s. I've registered interest in 3, O2, T-Mobile already.. you could call me a pre-register whore! ha!