Silly question: I have pre-order access why buy 4/28 release?

I have enjoyed the beta weekends over the last several months. Do I need to purchase the official 4/28 release to continue participating? I notice I can access Guild Wars today. Happy to support the excellent work by the development team and spend what is a reasonable sum - just want to understand the cut-over date. Thanks

The preorder key will work till midnight tonite. Then you will need the retail key to continue playing.

I believe the pre-order "thank you" days stop on Friday. They are just being really nice and giving us pre-order people Wednesday and Thursday to play without requiring a retail key until Friday.

Edit: Rizzen beat me

I am off today to buy the official release!