AT&T, the iPhone's carrier on the other side of the pond, has announced a two-tier data plan for its customers that, coincidentally, begins on the same day the iPhone 4G launch is expected - 7 June.

The plans are specially devised for either light or heavy users. On the DataPlus plan you'll get up to 200MB of 3G data for just $15 which is perfect if you only use your 3G connection for emailing, reading the news and the odd bit of online shopping. If you go over the limit then you'll just pay a further $15 for 200MB more.

For $25 you can get the DataPro plan. This will give you up to 2GB of 3G data, which AT&T says is enough for 98 per cent of its customers at the moment. If you do go over it's $10 per extra GB.

The announcement signals that AT&T are getting their house in order ahead of the iPhone 4G's launch especially as they have also confirmed that they will finally be offering tethering support for the new iPhone 4 OS when it becomes available.

"iPhone customers – who choose the DataPro plan have the option to add tethering for an additional $20 per month", says the mobile carrier.  

Tethering lets customers use their smartphones as a modem way to provide a broadband connection for laptop computers, netbooks or other computing devices and is something that although announced last year, has failed to make it to the consumer so far.

"Tethering for iPhones will be available when Apple releases iPhone OS 4 this summer", confirms AT&T.  

In the UK networks are still struggling to openly sell their data packages without confusion. Vodafone's data package is based around a 500MB plan that once reached charges you for another 500MB, but doesn't currently offer a tiered system to allow for low and high users alike.

Do you think O2, Orange, Vodafone, and 3 should offer a tiered system? Would you be happy to pay more for more data? Have your say in the comments below.