To get in the beta, you must send Yarlen 26 different pms, each one with a sentence beginning with a letter from A to Z. They must be in alphabetic order, rhyme, and be on topic.
For example...
Message 1: Acrobats love Sins and so do I,
Please let me give the beta a try!
Message 2: Because you're so cool and do cool things,
Let me beta test for you and give the Advent a fling.
Thats how I got in.