Immediately following the 3G iPhone announcement at 11:45a PST this morning, AT&T posted up a press release outlining all the great things Apple is doing for them. Oh, and they also snuck in a $10 increase for the unlimited iPhone data plan. The data price will be $30 instead of the current $20, plus voice. In essence, $69.95 and up for an iPhone plan. Add $10 more if you want a text plan. From AT&T:

• With a two-year contract, the price of an 8GB iPhone 3G will be $199; the 16GB model will be priced at $299.

• Unlimited iPhone 3G data plans for consumers will be available for $30 a month, in addition to voice plans starting at $39.99 a month.

• Unlimited 3G data plans for business users will be available for $45 a month, in addition to a voice plan.

Additionally, this may pose an issue to upgrading iPhone users, since potentially they won’t be able to take advantage of 3G without entering a new 2-year contract. This is not particularly surprising, particularly given all the recent AT&T 3G infrastructure improvement, but definitely a bit of a kick to the pants. It appears this increase may be across all data phones as well, including Windows Mobile and RIM Blackberry smartphones.

2:42pm Update: Gizmodo confirmed this with AT&T’s Glenn Lurie, plus you must activate the phone in store (Apple or AT&T). Ouch. At least that should keep the resale value of 1st gen iPhones relatively high.

AT&T: AT&T to Offer Next-Generation iPhone on Its High-Performance 3G Network