Such generosity and quick bug fixes are certainly rarities in the cell phone industry, so we're mighty impressed with Nokia right now. They've figured out the bug that's been causing the mysterious data connection drops and will have a software update that you can install using the Zune Desktop software or Windows Phone Connector "on or around Monday, April 16th". If that's not your cup of tea, you can take your Lumia into an ATT store for an exchange, but firmware updates via Zune are very easy.
Just in case that's not enough to sooth your data woes, Nokia has said "We apologize for any inconvenience this may have caused. As a gesture of good will, every individual who has already purchased a Nokia Lumia 900 — or who will purchase one between now and April 21st – will receive a $100 credit to their AT&T bill."
That brings the cost down to free for us early adopters who buy the Nokia Lumia 900 with a contract before April 21. Sweet. Thanks, Nokia!