http://www.subeta.net/cashshop.php?act=gold .

^ it says -help beta test new features- -supporting subeta- -a trophy for your lookup-

What do these three things mean?

Help subeta new features means like, when subeta is making something new. They go to you to try it out. Supporting subeta to stay on the web. And a trophy for becoming a gold member.

How often do you get to try things out?