You got lucky then. I tried to get in on a deal as an existing customer and got shot down. Also, the NEW CUSTOMER requirement is written in their Terms and Conditions. Important bits bolded.
Quote:
AT&T High Speed Internet Direct – DSL plans without AT&T home phone service.
$14.95/$19.95 Intro Pricing Promotion: Customers purchasing new AT&T High Speed Internet Direct Basic, Express or Pro will pay $14.95 per month for 12 months after application of bill credit. Customers purchasing AT&T High Speed Internet Direct Elite will pay $19.95 per month for 12 months after application of bill credit. First 2 credits will appear on same bill within the first 3 bill cycles. Promotional rates will expire if customer upgrades or downgrades their speed tier during promo period. On month 13 a $5/ mo. discount available to customers who: (1) have or purchase a qualifying Wireless plan from AT&T of $39.99 or higher at the time they order AT&T High Speed Internet, and (2) sign up for combined billing, or have the wireless and DSL Direct accounts under the same Billing Name, Service Address, and SSN. Residential customers only. Other conditions and restrictions apply. New DSL customers only. Offer expires 12/31/10.