As pointed out in another thread - the FAQ section of iPhone page in O2 website has now been updated. Something interesting i note: the EDGE/wiFi usage appears unlimited - i.e. no 200mb limit:
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What is the fair usage policy for the unlimited data and Wi-Fi?
Your O2 tariff for iPhone allows you unlimited use of O2 UKs Edge / GPRS networks and The Clouds UK Wireless LAN network, for personal internet use, email and Visual Voicemail (VVM) on your iPhone only. All usage must be for your private, personal and non-commercial purposes.
You may not use your SIM Card in any other device, or use your SIM Card or iPhone to allow the continuous streaming of any audio / video content, enable P2P or file sharing or use them in such a way that adversely impacts the service to other O2 customers.
If O2 reasonably suspect you are not acting in accordance with this policy O2 reserves the right to impose further charges or disconnect your tariff at any time, having attempted to contact you first.
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What is the fair usage policy for the unlimited data and Wi-Fi?
Your O2 tariff for iPhone allows you unlimited use of O2 UKs Edge / GPRS networks and The Clouds UK Wireless LAN network, for personal internet use, email and Visual Voicemail (VVM) on your iPhone only. All usage must be for your private, personal and non-commercial purposes.
You may not use your SIM Card in any other device, or use your SIM Card or iPhone to allow the continuous streaming of any audio / video content, enable P2P or file sharing or use them in such a way that adversely impacts the service to other O2 customers.
If O2 reasonably suspect you are not acting in accordance with this policy O2 reserves the right to impose further charges or disconnect your tariff at any time, having attempted to contact you first.